One feature of the DataSet is that if you can call multiple select statements in your stored procedures, the DataSet will have one DataTable for each.
Given a command like attrib:
require 'open3'
a="attrib"
Open3.popen3(a) do |stdin, stdout, stderr|
puts stdout.read
end
I've found that while this method isn't as memorable as
system("thecommand")
or
`thecommand`
in backticks, a good thing about this method compared to other methods is
backticks don't seem to let me puts the command I run/store the command I want to run in a variable, and system("thecommand") doesn't seem to let me get the output whereas this method lets me do both of those things, and it lets me access stdin, stdout and stderr independently.
See "Executing commands in ruby" and Ruby's Open3 documentation.
Yes, this is possible. One of the main pros for using Swing is the ease with which the abstract controls can be created and manipulates.
Here is a quick and dirty way to extend the existing JButton class to draw a circle to the right of the text.
package test;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import javax.swing.JButton;
import javax.swing.JFrame;
public class MyButton extends JButton {
private static final long serialVersionUID = 1L;
private Color circleColor = Color.BLACK;
public MyButton(String label) {
super(label);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension originalSize = super.getPreferredSize();
int gap = (int) (originalSize.height * 0.2);
int x = originalSize.width + gap;
int y = gap;
int diameter = originalSize.height - (gap * 2);
g.setColor(circleColor);
g.fillOval(x, y, diameter, diameter);
}
@Override
public Dimension getPreferredSize() {
Dimension size = super.getPreferredSize();
size.width += size.height;
return size;
}
/*Test the button*/
public static void main(String[] args) {
MyButton button = new MyButton("Hello, World!");
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
Container contentPane = frame.getContentPane();
contentPane.setLayout(new FlowLayout());
contentPane.add(button);
frame.setVisible(true);
}
}
Note that by overriding paintComponent that the contents of the button can be changed, but that the border is painted by the paintBorder method. The getPreferredSize method also needs to be managed in order to dynamically support changes to the content. Care needs to be taken when measuring font metrics and image dimensions.
For creating a control that you can rely on, the above code is not the correct approach. Dimensions and colours are dynamic in Swing and are dependent on the look and feel being used. Even the default Metal look has changed across JRE versions. It would be better to implement AbstractButton and conform to the guidelines set out by the Swing API. A good starting point is to look at the javax.swing.LookAndFeel and javax.swing.UIManager classes.
http://docs.oracle.com/javase/8/docs/api/javax/swing/LookAndFeel.html
http://docs.oracle.com/javase/8/docs/api/javax/swing/UIManager.html
Understanding the anatomy of LookAndFeel is useful for writing controls: Creating a Custom Look and Feel
I have found the solution else where:
SELECT SUBSTRING(master.dbo.fn_varbintohexstr(HashBytes('MD5', 'HelloWorld')), 3, 32)
In MVP, the Presenter contains the UI business logic for the View. All invocations from the View delegate directly to the Presenter. The Presenter is also decoupled directly from the View and talks to it through an interface. This is to allow mocking of the View in a unit test. One common attribute of MVP is that there has to be a lot of two-way dispatching. For example, when someone clicks the "Save" button, the event handler delegates to the Presenter's "OnSave" method. Once the save is completed, the Presenter will then call back the View through its interface so that the View can display that the save has completed.
MVP tends to be a very natural pattern for achieving separated presentation in WebForms. The reason is that the View is always created first by the ASP.NET runtime. You can find out more about both variants.
Passive View: The View is as dumb as possible and contains almost zero logic. A Presenter is a middle man that talks to the View and the Model. The View and Model are completely shielded from one another. The Model may raise events, but the Presenter subscribes to them for updating the View. In Passive View there is no direct data binding, instead, the View exposes setter properties that the Presenter uses to set the data. All state is managed in the Presenter and not the View.
Supervising Controller: The Presenter handles user gestures. The View binds to the Model directly through data binding. In this case, it's the Presenter's job to pass off the Model to the View so that it can bind to it. The Presenter will also contain logic for gestures like pressing a button, navigation, etc.
In the MVC, the Controller is responsible for determining which View to display in response to any action including when the application loads. This differs from MVP where actions route through the View to the Presenter. In MVC, every action in the View correlates with a call to a Controller along with an action. In the web, each action involves a call to a URL on the other side of which there is a Controller who responds. Once that Controller has completed its processing, it will return the correct View. The sequence continues in that manner throughout the life of the application:
Action in the View
-> Call to Controller
-> Controller Logic
-> Controller returns the View.
One other big difference about MVC is that the View does not directly bind to the Model. The view simply renders and is completely stateless. In implementations of MVC, the View usually will not have any logic in the code behind. This is contrary to MVP where it is absolutely necessary because, if the View does not delegate to the Presenter, it will never get called.
One other pattern to look at is the Presentation Model pattern. In this pattern, there is no Presenter. Instead, the View binds directly to a Presentation Model. The Presentation Model is a Model crafted specifically for the View. This means this Model can expose properties that one would never put on a domain model as it would be a violation of separation-of-concerns. In this case, the Presentation Model binds to the domain model and may subscribe to events coming from that Model. The View then subscribes to events coming from the Presentation Model and updates itself accordingly. The Presentation Model can expose commands which the view uses for invoking actions. The advantage of this approach is that you can essentially remove the code-behind altogether as the PM completely encapsulates all of the behavior for the view. This pattern is a very strong candidate for use in WPF applications and is also called Model-View-ViewModel.
There is a MSDN article about the Presentation Model and a section in the Composite Application Guidance for WPF (former Prism) about Separated Presentation Patterns
Top tip for new SVN users; this may help a little with getting the correct URLs quickly.
Run svn info to display useful information about the current checked-out branch.
The URL should (if you run svn in the root folder) give you the URL you need to copy from.
Also to switch to the newly created branch, use the svn switch command:
svn switch http://my.repo.url/myrepo/branches/newBranchName
I want to say something about the "G" status,
G: Changes on the repo were automatically merged into the working copy
I think the above definition is not cleary, it can generate a little confusion, because all files are automatically merged in to working copy, the correct one should be:
U = item (U)pdated to repository version
G = item’s local changes mer(G)ed with repository
C = item’s local changes (C)onflicted with repository
D = item (D)eleted from working copy
A = item (A)dded to working copy
Returns the system/OS name, such as 'Linux', 'Darwin', 'Java', 'Windows'. An empty string is returned if the value cannot be determined.
import platform
system = platform.system().lower()
is_windows = system == 'windows'
is_linux = system == 'linux'
is_mac = system == 'darwin'
If you are like me, who has no formal computer science education, and is interested in building/want to know how a compiler works:
I am recommend "Programming Language Processors in Java: Compilers and Interpreters", an amazing book for a self-taught computer programmer.
From my point of view, understanding those basic language theory, automate machine, and set theory is not a big problem. The problem is how to turn those things into code. The above book tells you how to write a parser, analysis context, and generate code. If you can not understand this book, then I have to say, give up building a compiler. The book is best programming book I have ever read.
There is an other book, also good, Compiler Design in C. There is a lot of code, and it tells you everything about how to build a compiler and lexer tools.
Building a compiler is a fun programming practice and can teach you heaps of programming skills.
Do not buy the Dragon book. It was a waste of money and time and is not for a practitioner.
Brian Deacon wrote:
Dvorak is so... Spolsky.
I can't describe why, but I agree.
I've tried this in Python 3.6.9
Convert Binary to Decimal
>>> 0b101111
47
>>> int('101111',2)
47
Convert Decimal to binary
>>> bin(47)
'0b101111'
Place a 0 as the second parameter python assumes it as decimal.
>>> int('101111',0)
101111
You can relocate it by editing the DocumentRoot setting in XAMPP\apache\conf\httpd.conf.
It should currently be:
C:/xampp/htdocs
Change it to:
C:/projects/transitCalculator/trunk
A variation of DixonD's excellent answer (above).
public static bool TryOpen(string path,
FileMode fileMode,
FileAccess fileAccess,
FileShare fileShare,
TimeSpan timeout,
out Stream stream)
{
var endTime = DateTime.Now + timeout;
while (DateTime.Now < endTime)
{
if (TryOpen(path, fileMode, fileAccess, fileShare, out stream))
return true;
}
stream = null;
return false;
}
public static bool TryOpen(string path,
FileMode fileMode,
FileAccess fileAccess,
FileShare fileShare,
out Stream stream)
{
try
{
stream = File.Open(path, fileMode, fileAccess, fileShare);
return true;
}
catch (IOException e)
{
if (!FileIsLocked(e))
throw;
stream = null;
return false;
}
}
private const uint HRFileLocked = 0x80070020;
private const uint HRPortionOfFileLocked = 0x80070021;
private static bool FileIsLocked(IOException ioException)
{
var errorCode = (uint)Marshal.GetHRForException(ioException);
return errorCode == HRFileLocked || errorCode == HRPortionOfFileLocked;
}
Usage:
private void Sample(string filePath)
{
Stream stream = null;
try
{
var timeOut = TimeSpan.FromSeconds(1);
if (!TryOpen(filePath,
FileMode.Open,
FileAccess.ReadWrite,
FileShare.ReadWrite,
timeOut,
out stream))
return;
// Use stream...
}
finally
{
if (stream != null)
stream.Close();
}
}
Performance can degrade in a matter of few thousand rows if database is not designed properly.
If you have proper indexes, use proper engines (don't use MyISAM where multiple DMLs are expected), use partitioning, allocate correct memory depending on the use and of course have good server configuration, MySQL can handle data even in terabytes!
There are always ways to improve the database performance.
Now, let’s say that we want to run a query to find all the details of any employees who are named ‘Abc’?
SELECT * FROM Employee
WHERE Employee_Name = 'Abc'
What would happen without an index?
Database software would literally have to look at every single row in the Employee table to see if the Employee_Name for that row is ‘Abc’. And, because we want every row with the name ‘Abc’ inside it, we can not just stop looking once we find just one row with the name ‘Abc’, because there could be other rows with the name Abc. So, every row up until the last row must be searched – which means thousands of rows in this scenario will have to be examined by the database to find the rows with the name ‘Abc’. This is what is called a full table scan
How a database index can help performance
The whole point of having an index is to speed up search queries by essentially cutting down the number of records/rows in a table that need to be examined. An index is a data structure (most commonly a B- tree) that stores the values for a specific column in a table.
How does B-trees index work?
The reason B- trees are the most popular data structure for indexes is due to the fact that they are time efficient – because look-ups, deletions, and insertions can all be done in logarithmic time. And, another major reason B- trees are more commonly used is because the data that is stored inside the B- tree can be sorted. The RDBMS typically determines which data structure is actually used for an index. But, in some scenarios with certain RDBMS’s, you can actually specify which data structure you want your database to use when you create the index itself.
How does a hash table index work?
The reason hash indexes are used is because hash tables are extremely efficient when it comes to just looking up values. So, queries that compare for equality to a string can retrieve values very fast if they use a hash index.
For instance, the query we discussed earlier could benefit from a hash index created on the Employee_Name column. The way a hash index would work is that the column value will be the key into the hash table and the actual value mapped to that key would just be a pointer to the row data in the table. Since a hash table is basically an associative array, a typical entry would look something like “Abc => 0x28939", where 0x28939 is a reference to the table row where Abc is stored in memory. Looking up a value like “Abc” in a hash table index and getting back a reference to the row in memory is obviously a lot faster than scanning the table to find all the rows with a value of “Abc” in the Employee_Name column.
The disadvantages of a hash index
Hash tables are not sorted data structures, and there are many types of queries which hash indexes can not even help with. For instance, suppose you want to find out all of the employees who are less than 40 years old. How could you do that with a hash table index? Well, it’s not possible because a hash table is only good for looking up key value pairs – which means queries that check for equality
What exactly is inside a database index? So, now you know that a database index is created on a column in a table, and that the index stores the values in that specific column. But, it is important to understand that a database index does not store the values in the other columns of the same table. For example, if we create an index on the Employee_Name column, this means that the Employee_Age and Employee_Address column values are not also stored in the index. If we did just store all the other columns in the index, then it would be just like creating another copy of the entire table – which would take up way too much space and would be very inefficient.
How does a database know when to use an index? When a query like “SELECT * FROM Employee WHERE Employee_Name = ‘Abc’ ” is run, the database will check to see if there is an index on the column(s) being queried. Assuming the Employee_Name column does have an index created on it, the database will have to decide whether it actually makes sense to use the index to find the values being searched – because there are some scenarios where it is actually less efficient to use the database index, and more efficient just to scan the entire table.
What is the cost of having a database index?
It takes up space – and the larger your table, the larger your index. Another performance hit with indexes is the fact that whenever you add, delete, or update rows in the corresponding table, the same operations will have to be done to your index. Remember that an index needs to contain the same up to the minute data as whatever is in the table column(s) that the index covers.
As a general rule, an index should only be created on a table if the data in the indexed column will be queried frequently.
See also
Since this question asked for non-Python versions, here's JavaScript:
a.methodname = function () { console.log("Yay, a new method!") }
Cool.
I also found the documentation regarding the E:
http://www.postgresql.org/docs/8.3/interactive/sql-syntax-lexical.html#SQL-SYNTAX-STRINGS
PostgreSQL also accepts "escape" string constants, which are an extension to the SQL standard. An escape string constant is specified by writing the letter E (upper or lower case) just before the opening single quote, e.g. E'foo'. (When continuing an escape string constant across lines, write E only before the first opening quote.) Within an escape string, a backslash character (\) begins a C-like backslash escape sequence, in which the combination of backslash and following character(s) represents a special byte value. \b is a backspace, \f is a form feed, \n is a newline, \r is a carriage return, \t is a tab. Also supported are \digits, where digits represents an octal byte value, and \xhexdigits, where hexdigits represents a hexadecimal byte value. (It is your responsibility that the byte sequences you create are valid characters in the server character set encoding.) Any other character following a backslash is taken literally. Thus, to include a backslash character, write two backslashes (\\). Also, a single quote can be included in an escape string by writing \', in addition to the normal way of ''.
1) I use print_r(). In TextMate, I have a snippet for 'pre' which expands to this:
echo "<pre>";
print_r();
echo "</pre>";
2) I use Xdebug, but haven't been able to get the GUI to work right on my Mac. It at least prints out a readable version of the stack trace.
It seems a lot of people get confused by the way objects are passed to functions and what passing by reference means. Object are still passed by value, it's just the value that is passed in PHP5 is a reference handle. As proof:
<?php
class Holder {
private $value;
public function __construct($value) {
$this->value = $value;
}
public function getValue() {
return $this->value;
}
}
function swap($x, $y) {
$tmp = $x;
$x = $y;
$y = $tmp;
}
$a = new Holder('a');
$b = new Holder('b');
swap($a, $b);
echo $a->getValue() . ", " . $b->getValue() . "\n";
Outputs:
a, b
To pass by reference means we can modify the variables that are seen by the caller, which clearly the code above does not do. We need to change the swap function to:
<?php
function swap(&$x, &$y) {
$tmp = $x;
$x = $y;
$y = $tmp;
}
$a = new Holder('a');
$b = new Holder('b');
swap($a, $b);
echo $a->getValue() . ", " . $b->getValue() . "\n";
Outputs:
b, a
in order to pass by reference.
I absolutely love being able to manage local branches of my source code in Git without muddying up the water of the central repository. In many cases I'll checkout code from the Subversion server and run a local Git repository just to be able to do this. It's also great that initializing a Git repository doesn't pollute the filesystem with a bunch of annoying .svn folders everywhere.
And as far as Windows tool support, TortoiseGit handles the basics very well, but I still prefer the command line unless I want to view the log. I really like the way Tortoise{Git|SVN} helps when reading commit logs.
IMPORTANT NOTE: You have to sort your data first.
The part I didn't get is that in the example construction
groups = []
uniquekeys = []
for k, g in groupby(data, keyfunc):
groups.append(list(g)) # Store group iterator as a list
uniquekeys.append(k)
k is the current grouping key, and g is an iterator that you can use to iterate over the group defined by that grouping key. In other words, the groupby iterator itself returns iterators.
Here's an example of that, using clearer variable names:
from itertools import groupby
things = [("animal", "bear"), ("animal", "duck"), ("plant", "cactus"), ("vehicle", "speed boat"), ("vehicle", "school bus")]
for key, group in groupby(things, lambda x: x[0]):
for thing in group:
print("A %s is a %s." % (thing[1], key))
print("")
This will give you the output:
A bear is a animal.
A duck is a animal.A cactus is a plant.
A speed boat is a vehicle.
A school bus is a vehicle.
In this example, things is a list of tuples where the first item in each tuple is the group the second item belongs to.
The groupby() function takes two arguments: (1) the data to group and (2) the function to group it with.
Here, lambda x: x[0] tells groupby() to use the first item in each tuple as the grouping key.
In the above for statement, groupby returns three (key, group iterator) pairs - once for each unique key. You can use the returned iterator to iterate over each individual item in that group.
Here's a slightly different example with the same data, using a list comprehension:
for key, group in groupby(things, lambda x: x[0]):
listOfThings = " and ".join([thing[1] for thing in group])
print(key + "s: " + listOfThings + ".")
This will give you the output:
animals: bear and duck.
plants: cactus.
vehicles: speed boat and school bus.
The Activator class within the root System namespace is pretty powerful.
There are a lot of overloads for passing parameters to the constructor and such. Check out the documentation at:
http://msdn.microsoft.com/en-us/library/system.activator.createinstance.aspx
or (new path)
https://docs.microsoft.com/en-us/dotnet/api/system.activator.createinstance
Here are some simple examples:
ObjectType instance = (ObjectType)Activator.CreateInstance(objectType);
ObjectType instance = (ObjectType)Activator.CreateInstance("MyAssembly","MyNamespace.ObjectType");
int is used to declare primitive variable
e.g. int i=10;
Integer is used to create reference variable of class Integer
Integer a = new Integer();
When hashing, don't use fast hash algorithms such as MD5 (many hardware implementations exist). Use something like SHA-512. For passwords, slower hashes are better.
The faster you can create hashes, the faster any brute force checker can work. Slower hashes will therefore slow down brute forcing. A slow hash algorithm will make brute forcing impractical for longer passwords (8 digits +)
Confirm that you have the correct email address before sending out emails. If someone gives the wrong email address on sign-up, beat them over the head about it ASAP.
Always include clear "how to unsubscribe" information in EVERY email. Do not require the user to login to unsubscribe, it should be a unique url for 1-click unsubscribe.
This will prevent people from marking your mails as spam because "unsubscribing" is too hard.
Here is a link that describes how to print permutations of a string. http://nipun-linuxtips.blogspot.in/2012/11/print-all-permutations-of-characters-in.html
Use LINQ:
Dictionary<string, int> myDict = new Dictionary<string, int>();
myDict.Add("one", 1);
myDict.Add("four", 4);
myDict.Add("two", 2);
myDict.Add("three", 3);
var sortedDict = from entry in myDict orderby entry.Value ascending select entry;
This would also allow for great flexibility in that you can select the top 10, 20 10%, etc. Or if you are using your word frequency index for type-ahead, you could also include StartsWith clause as well.
The default behaviour for error_log() is to output to the Apache error log. If this isn't happening check your php.ini settings for the error_log directive. Leave it unset to use the Apache log file for the current vhost.
Here at Red Gate we offer a tool, SQL Source Control, which uses SQL Compare technology to link your database with a TFS or SVN repository. This tool integrates into SSMS and lets you work as you would normally, except it now lets you commit the objects.
For a migrations-based approach (more suited for automated deployments), we offer SQL Change Automation (formerly called ReadyRoll), which creates and manages a set of incremental scripts as a Visual Studio project.
In SQL Source Control it is possible to specify static data tables. These are stored in source control as INSERT statements.
If you're talking about test data, we'd recommend that you either generate test data with a tool or via a post-deployment script you define, or you simply restore a production backup to the dev environment.
Use the following. It works in Firefox and Internet Explorer.
<object id="MediaPlayer1" width="690" height="500" classid="CLSID:22D6F312-B0F6-11D0-94AB-0080C74C7E95"
codebase="http://activex.microsoft.com/activex/controls/mplayer/en/nsmp2inf.cab#Version=5,1,52,701"
standby="Loading Microsoft® Windows® Media Player components..." type="application/x-oleobject"
>
<param name="FileName" value='<%= GetSource() %>' />
<param name="AutoStart" value="True" />
<param name="DefaultFrame" value="mainFrame" />
<param name="ShowStatusBar" value="0" />
<param name="ShowPositionControls" value="0" />
<param name="showcontrols" value="0" />
<param name="ShowAudioControls" value="0" />
<param name="ShowTracker" value="0" />
<param name="EnablePositionControls" value="0" />
<!-- BEGIN PLUG-IN HTML FOR FIREFOX-->
<embed type="application/x-mplayer2" pluginspage="http://www.microsoft.com/Windows/MediaPlayer/"
src='<%= GetSource() %>' align="middle" width="600" height="500" defaultframe="rightFrame"
id="MediaPlayer2" />
And in JavaScript,
function playVideo() {
try{
if(-1 != navigator.userAgent.indexOf("MSIE"))
{
var obj = document.getElementById("MediaPlayer1");
obj.Play();
}
else
{
var player = document.getElementById("MediaPlayer2");
player.controls.play();
}
}
catch(error) {
alert(error)
}
}
From https://html.spec.whatwg.org/multipage/forms.html#implicit-submission
A form element's default button is the first submit button in tree order whose form owner is that form element.
If the user agent supports letting the user submit a form implicitly (for example, on some platforms hitting the "enter" key while a text field is focused implicitly submits the form)...
Having the next input be type="submit" and changing the previous input to type="button" should give the desired default behavior.
<form>
<input type="text" name="field1" /> <!-- put your cursor in this field and press Enter -->
<input type="button" name="prev" value="Previous Page" /> <!-- This is the button that will submit -->
<input type="submit" name="next" value="Next Page" /> <!-- But this is the button that I WANT to submit -->
</form>
Math.Floor rounds down, Math.Ceiling rounds up, and Math.Truncate rounds towards zero. Thus, Math.Truncate is like Math.Floor for positive numbers, and like Math.Ceiling for negative numbers. Here's the reference.
For completeness, Math.Round rounds to the nearest integer. If the number is exactly midway between two integers, then it rounds towards the even one. Reference.
See also: Pax Diablo's answer. Highly recommended!
A couple of years late to the party, but I had a requirement to do this for both past and future dates, so I combined Jeff's and Vincent's into this. It's a ternarytastic extravaganza! :)
public static class DateTimeHelper
{
private const int SECOND = 1;
private const int MINUTE = 60 * SECOND;
private const int HOUR = 60 * MINUTE;
private const int DAY = 24 * HOUR;
private const int MONTH = 30 * DAY;
/// <summary>
/// Returns a friendly version of the provided DateTime, relative to now. E.g.: "2 days ago", or "in 6 months".
/// </summary>
/// <param name="dateTime">The DateTime to compare to Now</param>
/// <returns>A friendly string</returns>
public static string GetFriendlyRelativeTime(DateTime dateTime)
{
if (DateTime.UtcNow.Ticks == dateTime.Ticks)
{
return "Right now!";
}
bool isFuture = (DateTime.UtcNow.Ticks < dateTime.Ticks);
var ts = DateTime.UtcNow.Ticks < dateTime.Ticks ? new TimeSpan(dateTime.Ticks - DateTime.UtcNow.Ticks) : new TimeSpan(DateTime.UtcNow.Ticks - dateTime.Ticks);
double delta = ts.TotalSeconds;
if (delta < 1 * MINUTE)
{
return isFuture ? "in " + (ts.Seconds == 1 ? "one second" : ts.Seconds + " seconds") : ts.Seconds == 1 ? "one second ago" : ts.Seconds + " seconds ago";
}
if (delta < 2 * MINUTE)
{
return isFuture ? "in a minute" : "a minute ago";
}
if (delta < 45 * MINUTE)
{
return isFuture ? "in " + ts.Minutes + " minutes" : ts.Minutes + " minutes ago";
}
if (delta < 90 * MINUTE)
{
return isFuture ? "in an hour" : "an hour ago";
}
if (delta < 24 * HOUR)
{
return isFuture ? "in " + ts.Hours + " hours" : ts.Hours + " hours ago";
}
if (delta < 48 * HOUR)
{
return isFuture ? "tomorrow" : "yesterday";
}
if (delta < 30 * DAY)
{
return isFuture ? "in " + ts.Days + " days" : ts.Days + " days ago";
}
if (delta < 12 * MONTH)
{
int months = Convert.ToInt32(Math.Floor((double)ts.Days / 30));
return isFuture ? "in " + (months <= 1 ? "one month" : months + " months") : months <= 1 ? "one month ago" : months + " months ago";
}
else
{
int years = Convert.ToInt32(Math.Floor((double)ts.Days / 365));
return isFuture ? "in " + (years <= 1 ? "one year" : years + " years") : years <= 1 ? "one year ago" : years + " years ago";
}
}
}
I have a customized method to calculate age, plus a bonus validation message just in case it helps:
public void GetAge(DateTime dob, DateTime now, out int years, out int months, out int days)
{
years = 0;
months = 0;
days = 0;
DateTime tmpdob = new DateTime(dob.Year, dob.Month, 1);
DateTime tmpnow = new DateTime(now.Year, now.Month, 1);
while (tmpdob.AddYears(years).AddMonths(months) < tmpnow)
{
months++;
if (months > 12)
{
years++;
months = months - 12;
}
}
if (now.Day >= dob.Day)
days = days + now.Day - dob.Day;
else
{
months--;
if (months < 0)
{
years--;
months = months + 12;
}
days += DateTime.DaysInMonth(now.AddMonths(-1).Year, now.AddMonths(-1).Month) + now.Day - dob.Day;
}
if (DateTime.IsLeapYear(dob.Year) && dob.Month == 2 && dob.Day == 29 && now >= new DateTime(now.Year, 3, 1))
days++;
}
private string ValidateDate(DateTime dob) //This method will validate the date
{
int Years = 0; int Months = 0; int Days = 0;
GetAge(dob, DateTime.Now, out Years, out Months, out Days);
if (Years < 18)
message = Years + " is too young. Please try again on your 18th birthday.";
else if (Years >= 65)
message = Years + " is too old. Date of Birth must not be 65 or older.";
else
return null; //Denotes validation passed
}
Method call here and pass out datetime value (MM/dd/yyyy if server set to USA locale). Replace this with anything a messagebox or any container to display:
DateTime dob = DateTime.Parse("03/10/1982");
string message = ValidateDate(dob);
lbldatemessage.Visible = !StringIsNullOrWhitespace(message);
lbldatemessage.Text = message ?? ""; //Ternary if message is null then default to empty string
Remember you can format the message any way you like.
None of the answer works for me on Wordpress website but following works ( it's similar to other answers but have a little change)
RewriteEngine On
RewriteCond %{HTTPS} on
RewriteRule (.*) http://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
You can open the file, go to 0 offset relative from the bottom of the file with
#define SEEKBOTTOM 2
fseek(handle, 0, SEEKBOTTOM)
the value returned from fseek is the size of the file.
I didn't code in C for a long time, but I think it should work.
Here's some code. This assumes you are doing this on a form, or a UserControl.
Graphics g = this.CreateGraphics();
SizeF size = g.MeasureString("string to measure");
int nLeft = Convert.ToInt32((this.ClientRectangle.Width / 2) - (size.Width / 2));
int nTop = Convert.ToInt32((this.ClientRectangle.Height / 2) - (size.Height / 2));
From your post, it sounds like the ClientRectangle part (as in, you're not using it) is what's giving you difficulty.
#include <iostream>
#include <fstream>
using namespace std;
void main()
{
ifstream in_stream; // fstream command to initiate "in_stream" as a command.
char filename[31]; // variable for "filename".
cout << "Enter file name to open :: "; // asks user for input for "filename".
cin.getline(filename, 30); // this gets the line from input for "filename".
in_stream.open(filename); // this in_stream (fstream) the "filename" to open.
if (in_stream.fail())
{
cout << "Could not open file to read.""\n"; // if the open file fails.
return;
}
//.....the rest of the text goes beneath......
}
Continuing with what Dave Ward said:
Page/Control design
<asp:Label runat="server" ID="Label1" Style="display: none;" />
<asp:Button runat="server" ID="Button1" />
Code behind
Somewhere in the load section:
Label label1 = (Label)FindControl("Label1");
((Label)FindControl("Button1")).OnClientClick = "ToggleVisibility('" + label1.ClientID + "')";
Javascript file
function ToggleVisibility(elementID)
{
var element = document.getElementByID(elementID);
if (element.style.display = 'none')
{
element.style.display = 'inherit';
}
else
{
element.style.display = 'none';
}
}
Of course, if you don't want to toggle but just to show the button/label then adjust the javascript method accordingly.
The important point here is that you need to send the information about the ClientID of the control that you want to manipulate on the client side to the javascript file either setting global variables or through a function parameter as in my example.
Use this for windows Server 2008 r2 and Windows Server 2012 R2
Click Start, click Run, type dcomcnfg and then click OK to open Component Services.
In the console tree, click to expand Component Services, click to expand Computers, click to expand My Computer, click to expand Distributed Transaction Coordinator and then click Local DTC.
Right click Local DTC and click Properties to display the Local DTC Properties dialog box.
Click the Security tab.
Check mark "Network DTC Access" checkbox.
Finally check mark "Allow Inbound" and "Allow Outbound" checkboxes.
Click Apply, OK.
A message will pop up about restarting the service.
Click OK and That's all.
Reference : https://msdn.microsoft.com/en-us/library/dd327979.aspx
Note: Sometimes the network firewall on the Local Computer or the Server could interrupt your connection so make sure you create rules to "Allow Inbound" and "Allow Outbound" connection for C:\Windows\System32\msdtc.exe
readlink -f "$path"
Editor's note: The above works with GNU readlink and FreeBSD/PC-BSD/OpenBSD readlink, but not on OS X as of 10.11.
GNU readlink offers additional, related options, such as -m for resolving a symlink whether or not the ultimate target exists.
Note since GNU coreutils 8.15 (2012-01-06), there is a realpath program available that is less obtuse and more flexible than the above. It's also compatible with the FreeBSD util of the same name. It also includes functionality to generate a relative path between two files.
realpath $path
[Admin addition below from comment by halloleo —danorton]
For Mac OS X (through at least 10.11.x), use readlink without the -f option:
readlink $path
Editor's note: This will not resolve symlinks recursively and thus won't report the ultimate target; e.g., given symlink a that points to b, which in turn points to c, this will only report b (and won't ensure that it is output as an absolute path).
Use the following perl command on OS X to fill the gap of the missing readlink -f functionality:
perl -MCwd -le 'print Cwd::abs_path(shift)' "$path"
Take a look at ISO 11179-5: Naming and identification principles You can get it here: http://metadata-standards.org/11179/#11179-5
I blogged about it a while back here: ISO-11179 Naming Conventions
Can be done with a simple Perl one liner.
my @in=qw(1 3 4 6 2 4 3 2 6 3 2 3 4 4 3 2 5 5 32 3); #Sample data
my @out=keys %{{ map{$_=>1}@in}}; # Perform PFM
print join ' ', sort{$a<=>$b} @out;# Print data back out sorted and in order.
The PFM block does this:
Data in @in is fed into MAP. MAP builds an anonymous hash. Keys are extracted from the hash and feed into @out
Consider i and n to be the left and right operands respectively of a shift operator; the type of i, after integer promotion, be T. Assuming n to be in [0, sizeof(i) * CHAR_BIT) — undefined otherwise — we've these cases:
| Direction | Type | Value (i) | Result |
| ---------- | -------- | --------- | ------------------------ |
| Right (>>) | unsigned | = 0 | -8 ? (i ÷ 2n) |
| Right | signed | = 0 | -8 ? (i ÷ 2n) |
| Right | signed | < 0 | Implementation-defined† |
| Left (<<) | unsigned | = 0 | (i * 2n) % (T_MAX + 1) |
| Left | signed | = 0 | (i * 2n) ‡ |
| Left | signed | < 0 | Undefined |
† most compilers implement this as arithmetic shift
‡ undefined if value overflows the result type T; promoted type of i
First is the difference between logical and arithmetic shifts from a mathematical viewpoint, without worrying about data type size. Logical shifts always fills discarded bits with zeros while arithmetic shift fills it with zeros only for left shift, but for right shift it copies the MSB thereby preserving the sign of the operand (assuming a two's complement encoding for negative values).
In other words, logical shift looks at the shifted operand as just a stream of bits and move them, without bothering about the sign of the resulting value. Arithmetic shift looks at it as a (signed) number and preserves the sign as shifts are made.
A left arithmetic shift of a number X by n is equivalent to multiplying X by 2n and is thus equivalent to logical left shift; a logical shift would also give the same result since MSB anyway falls off the end and there's nothing to preserve.
A right arithmetic shift of a number X by n is equivalent to integer division of X by 2n ONLY if X is non-negative! Integer division is nothing but mathematical division and round towards 0 (trunc).
For negative numbers, represented by two's complement encoding, shifting right by n bits has the effect of mathematically dividing it by 2n and rounding towards -8 (floor); thus right shifting is different for non-negative and negative values.
for X = 0, X >> n = X / 2n = trunc(X ÷ 2n)
for X < 0, X >> n = floor(X ÷ 2n)
where ÷ is mathematical division, / is integer division. Let's look at an example:
37)10 = 100101)2
37 ÷ 2 = 18.5
37 / 2 = 18 (rounding 18.5 towards 0) = 10010)2 [result of arithmetic right shift]
-37)10 = 11011011)2 (considering a two's complement, 8-bit representation)
-37 ÷ 2 = -18.5
-37 / 2 = -18 (rounding 18.5 towards 0) = 11101110)2 [NOT the result of arithmetic right shift]
-37 >> 1 = -19 (rounding 18.5 towards -8) = 11101101)2 [result of arithmetic right shift]
As Guy Steele pointed out, this discrepancy has led to bugs in more than one compiler. Here non-negative (math) can be mapped to unsigned and signed non-negative values (C); both are treated the same and right-shifting them is done by integer division.
So logical and arithmetic are equivalent in left-shifting and for non-negative values in right shifting; it's in right shifting of negative values that they differ.
Standard C99 §6.5.7:
Each of the operands shall have integer types.
The integer promotions are performed on each of the operands. The type of the result is that of the promoted left operand. If the value of the right operand is negative or is greater than or equal to the width of the promoted left operand, the behaviour is undefined.
short E1 = 1, E2 = 3;
int R = E1 << E2;
In the above snippet, both operands become int (due to integer promotion); if E2 was negative or E2 = sizeof(int) * CHAR_BIT then the operation is undefined. This is because shifting more than the available bits is surely going to overflow. Had R been declared as short, the int result of the shift operation would be implicitly converted to short; a narrowing conversion, which may lead to implementation-defined behaviour if the value is not representable in the destination type.
The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated bits are filled with zeros. If E1 has an unsigned type, the value of the result is E1×2E2, reduced modulo one more than the maximum value representable in the result type. If E1 has a signed type and non-negative value, and E1×2E2 is representable in the result type, then that is the resulting value; otherwise, the behaviour is undefined.
As left shifts are the same for both, the vacated bits are simply filled with zeros. It then states that for both unsigned and signed types it's an arithmetic shift. I'm interpreting it as arithmetic shift since logical shifts don't bother about the value represented by the bits, it just looks at it as a stream of bits; but the standard talks not in terms of bits, but by defining it in terms of the value obtained by the product of E1 with 2E2.
The caveat here is that for signed types the value should be non-negative and the resulting value should be representable in the result type. Otherwise the operation is undefined. The result type would be the type of the E1 after applying integral promotion and not the destination (the variable which is going to hold the result) type. The resulting value is implicitly converted to the destination type; if it is not representable in that type, then the conversion is implementation-defined (C99 §6.3.1.3/3).
If E1 is a signed type with a negative value then the behaviour of left shifting is undefined. This is an easy route to undefined behaviour which may easily get overlooked.
The result of E1 >> E2 is E1 right-shifted E2 bit positions. If E1 has an unsigned type or if E1 has a signed type and a non-negative value, the value of the result is the integral part of the quotient of E1/2E2. If E1 has a signed type and a negative value, the resulting value is implementation-defined.
Right shift for unsigned and signed non-negative values are pretty straight forward; the vacant bits are filled with zeros. For signed negative values the result of right shifting is implementation-defined. That said, most implementations like GCC and Visual C++ implement right-shifting as arithmetic shifting by preserving the sign bit.
Unlike Java, which has a special operator >>> for logical shifting apart from the usual >> and <<, C and C++ have only arithmetic shifting with some areas left undefined and implementation-defined. The reason I deem them as arithmetic is due to the standard wording the operation mathematically rather than treating the shifted operand as a stream of bits; this is perhaps the reason why it leaves those areas un/implementation-defined instead of just defining all cases as logical shifts.
There is a great checklist found on Github:
Authentication
Don't reinvent the wheel in Authentication, token generation, password storage. Use the standards.
Use Max Retry and jail features in Login.
Use encryption on all sensitive data.
JWT (JSON Web Token)
Use a random complicated key (JWT Secret) to make brute forcing the token very hard.
Don't extract the algorithm from the payload. Force the algorithm in the backend (HS256 or RS256).
Make token expiration (TTL, RTTL) as short as possible.
Don't store sensitive data in the JWT payload, it can be decoded easily.
OAuth
Always validate redirect_uri server-side to allow only whitelisted URLs.
Always try to exchange for code and not tokens (don't allow response_type=token).
Use state parameter with a random hash to prevent CSRF on the OAuth authentication process.
Define the default scope, and validate scope parameters for each application.
Access
Limit requests (Throttling) to avoid DDoS / brute-force attacks.
Use HTTPS on server side to avoid MITM (Man In The Middle Attack)
Use HSTS header with SSL to avoid SSL Strip attack.
Input
Use the proper HTTP method according to the operation: GET (read), POST (create), PUT/PATCH (replace/update), and DELETE (to delete a record), and respond with 405 Method Not Allowed if the requested method isn't appropriate for the requested resource.
Validate content-type on request Accept header (Content Negotiation) to allow only your supported format (e.g. application/xml, application/json, etc) and respond with 406 Not Acceptable response if not matched.
Validate content-type of posted data as you accept (e.g. application/x-www-form-urlencoded, multipart/form-data, application/json, etc).
Validate User input to avoid common vulnerabilities (e.g. XSS, SQL-Injection, Remote Code Execution, etc).
Don't use any sensitive data (credentials, Passwords, security tokens, or API keys) in the URL, but use standard Authorization header.
Use an API Gateway service to enable caching, Rate Limit policies (e.g. Quota, Spike Arrest, Concurrent Rate Limit) and deploy APIs resources dynamically.
Processing
Check if all the endpoints are protected behind authentication to avoid broken authentication process.
User own resource ID should be avoided. Use /me/orders instead of /user/654321/orders.
Don't auto-increment IDs. Use UUID instead.
If you are parsing XML files, make sure entity parsing is not enabled to avoid XXE (XML external entity attack).
If you are parsing XML files, make sure entity expansion is not enabled to avoid Billion Laughs/XML bomb via exponential entity expansion attack.
Use a CDN for file uploads.
If you are dealing with huge amount of data, use Workers and Queues to process as much as possible in background and return response fast to avoid HTTP Blocking.
Do not forget to turn the DEBUG mode OFF.
Output
Send X-Content-Type-Options: nosniff header.
Send X-Frame-Options: deny header.
Send Content-Security-Policy: default-src 'none' header.
Remove fingerprinting headers - X-Powered-By, Server, X-AspNet-Version etc.
Force content-type for your response, if you return application/json then your response content-type is application/json.
Don't return sensitive data like credentials, Passwords, security tokens.
Return the proper status code according to the operation completed. (e.g. 200 OK, 400 Bad Request, 401 Unauthorized, 405 Method Not Allowed, etc).
I vote for jMeter too and I want add some quotes to @PeterBernier answer.
The main question that load testing answers is how many concurrent users can my web application support? In order to get a proper answer, load testing should represent real application usage, as close as possible.
Keep above in mind, jMeter has many building blocks Logical Controllers, Config Elements, Pre Processors, Listeners ,... which can help you in this.
You can mimic real world situation with jMeter, for example you can:
concurrent resource download, browser cache, http headers, setting request time out, cookie management, https support, encoding , ajax support ,... ) number of users per second, ramp-up time, scheduling ,...)assert response to find a text in it)Please consider:
HTTP(S) Test Script Recorder).listeners) but there are not meant to be on during test. You must run your test and generate reports ( .jtl files). Then you must use these tools to analyze result. Please have a look at https://www.blazemeter.com/blog/jmeter-listeners-part-1-basic-display-formats or https://www.tutorialspoint.com/jmeter/jmeter_listeners.htm.The https://www.blazemeter.com/jmeter has very good and practical information to help you configure your test environment.
Probably the shortest solution:
jQuery(document).ready(function(){
jQuery("#textArea").on("keydown keyup", function(){
this.style.height = "1px";
this.style.height = (this.scrollHeight) + "px";
});
});
This way you don't need any hidden divs or anything like that.
Note: you might have to play with this.style.height = (this.scrollHeight) + "px"; depending on how you style the textarea (line-height, padding and that kind of stuff).
<?php
//getting new instance
$pdfFile = new_pdf();
PDF_open_file($pdfFile, " ");
//document info
pdf_set_info($pdfFile, "Auther", "Ahmed Elbshry");
pdf_set_info($pdfFile, "Creator", "Ahmed Elbshry");
pdf_set_info($pdfFile, "Title", "PDFlib");
pdf_set_info($pdfFile, "Subject", "Using PDFlib");
//starting our page and define the width and highet of the document
pdf_begin_page($pdfFile, 595, 842);
//check if Arial font is found, or exit
if($font = PDF_findfont($pdfFile, "Arial", "winansi", 1)) {
PDF_setfont($pdfFile, $font, 12);
} else {
echo ("Font Not Found!");
PDF_end_page($pdfFile);
PDF_close($pdfFile);
PDF_delete($pdfFile);
exit();
}
//start writing from the point 50,780
PDF_show_xy($pdfFile, "This Text In Arial Font", 50, 780);
PDF_end_page($pdfFile);
PDF_close($pdfFile);
//store the pdf document in $pdf
$pdf = PDF_get_buffer($pdfFile);
//get the len to tell the browser about it
$pdflen = strlen($pdfFile);
//telling the browser about the pdf document
header("Content-type: application/pdf");
header("Content-length: $pdflen");
header("Content-Disposition: inline; filename=phpMade.pdf");
//output the document
print($pdf);
//delete the object
PDF_delete($pdfFile);
?>
Here is the simplest explanation
Alan Turing created a machine that can take a program, run that program, and show some result. But then he had to create different machines for different programs. So he created "Universal Turing Machine" that can take ANY program and run it.
Programming languages are similar to those machines (although virtual). They take programs and run them. Now, a programing language is called "Turing complete", if it can run any program (irrespective of the language) that a Turing machine can run given enough time and memory.
For example: Let's say there is a program that takes 10 numbers and adds them. A Turing machine can easily run this program. But now imagine that for some reason your programming language can't perform the same addition. This would make it "Turing incomplete" (so to speak). On the other hand, if it can run any program that the universal Turing machine can run, then it's Turing complete.
Most modern programming languages (e.g. Java, JavaScript, Perl, etc.) are all Turing complete because they each implement all the features required to run programs like addition, multiplication, if-else condition, return statements, ways to store/retrieve/erase data and so on.
Update: You can learn more on my blog post: "JavaScript Is Turing Complete" — Explained
String : Represent a class
string : Represent an alias
It's just a coding convention from microsoft .
The zenity application appears to be what you are looking for.
To take input from zenity, you can specify a variable and have the output of zenity --entry saved to it. It looks something like this:
my_variable=$(zenity --entry)
If you look at the value in my_variable now, it will be whatever was typed in the zenity pop up entry dialog.
If you want to give some sort of prompt as to what the user (or you) should enter in the dialog, add the --text switch with the label that you want. It looks something like this:
my_variable=$(zenity --entry --text="What's my variable:")
Zenity has lot of other nice options that are for specific tasks, so you might want to check those out as well with zenity --help. One example is the --calendar option that let's you select a date from a graphical calendar.
my_date=$(zenity --calendar)
Which gives a nicely formatted date based on what the user clicked on:
echo ${my_date}
gives:
08/05/2009
There are also options for slider selectors, errors, lists and so on.
Hope this helps.
As guruz mentioned, the JIT has several lovely graph/tree layouts, including quite appealing RGraph and HyperTree visualizations.
Also, I've just put up a super simple SVG-based implementation at github (no dependencies, ~125 LOC) that should work well enough for small graphs displayed in modern browsers.
Try this query
SELECT v.VehicleId, v.Name, ll.LocationList
FROM Vehicles v
LEFT JOIN
(SELECT
DISTINCT
VehicleId,
REPLACE(
REPLACE(
REPLACE(
(
SELECT City as c
FROM Locations x
WHERE x.VehicleID = l.VehicleID FOR XML PATH('')
),
'</c><c>',', '
),
'<c>',''
),
'</c>', ''
) AS LocationList
FROM Locations l
) ll ON ll.VehicleId = v.VehicleId
What are you loading the files for - configuration or data (like an input file) or as a resource?
BufferedReader file = new BufferedReader(new FileReader(filename)) and then read each line of the file using file.readLine(); Don't forget to close the file.As for other languages:
'VB
For i=0 To 10
If i=5 then Exit For '= break in C#;
'Do Something for i<5
next
For i=0 To 10
If i=5 then Continue For '= continue in C#
'Do Something for i<>5...
Next
you can use log4net.Filter.LevelMatchFilter. other options can be found at log4net tutorial - filters
in ur appender section add
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="Info" />
<acceptOnMatch value="true" />
</filter>
the accept on match default is true so u can leave it out but if u set it to false u can filter out log4net filters
This should return the text value of the selected value
var vSkill = document.getElementById('newSkill');
var vSkillText = vSkill.options[vSkill.selectedIndex].innerHTML;
alert(vSkillText);
Props: @Tanerax for reading the question, knowing what was asked and answering it before others figured it out.
Edit: DownModed, cause I actually read a question fully, and answered it, sad world it is.
I had a similar issue using like pattern '%_%' did not work - as the question indicates :-)
Using '%\_%' did not work either as this first \ is interpreted "before the like".
Using '%\\_%' works. The \\ (double backslash) is first converted to single \ (backslash) and then used in the like pattern.
IsNothing()Here are 4 reasons from the article IsNothing() VS Is Nothing
Most importantly, IsNothing(object) has everything passed to it as an object, even value types! Since value types cannot be Nothing, it’s a completely wasted check.
Take the following example:
Dim i As Integer
If IsNothing(i) Then
' Do something
End If
This will compile and run fine, whereas this:
Dim i As Integer
If i Is Nothing Then
' Do something
End If
Will not compile, instead the compiler will raise the error:
'Is' operator does not accept operands of type 'Integer'.
Operands must be reference or nullable types.
IsNothing(object) is actually part of part of the Microsoft.VisualBasic.dll.
This is undesirable as you have an unneeded dependency on the VisualBasic library.
Its slow - 33.76% slower in fact (over 1000000000 iterations)!
Perhaps personal preference, but IsNothing() reads like a Yoda Condition. When you look at a variable you're checking it's state, with it as the subject of your investigation.
i.e. does it do x? --- NOT Is xing a property of it?
So I think If a IsNot Nothing reads better than If Not IsNothing(a)
In case you're inside a Sub of Function and you want to exit it, you can use :
Exit Sub
or
Exit Function
If you are to encounter the error that says Microsoft.CSharp.Core.targets not found, these are the steps I took to correct mine:
Open any previous working projects folder and navigate to the link showed in the error, that is Projects/(working project name)/packages/Microsoft.Net.Compilers.1.3.2/tools/ and search for Microsoft.CSharp.Core.targets file.
Copy this file and put it in the non-working project tools folder (that is, navigating to the tools folder in the non-working project as shown above)
Now close your project (if it was open) and reopen it.
It should be working now.
Also, to make sure everything is working properly in your now open Visual Studio Project, Go to Tools > NuGetPackage Manager > Manage NuGet Packages For Solution. Here, you might find an error that says, CodeAnalysis.dll is being used by another application.
Again, go to the tools folder, find the specified file and delete it. Come back to Manage NuGet Packages For Solution. You will find a link that will ask you to Reload, click it and everything gets re-installed.
Your project should be working properly now.
As stated before, don't use syscall. You can use standard C library calls though, but be aware that the stack MUST be 16 byte aligned per Apple's IA32 function call ABI.
If you don't align the stack, your program will crash in __dyld_misaligned_stack_error when you make a call into any of the libraries or frameworks.
The following snippet assembles and runs on my system:
; File: hello.asm
; Build: nasm -f macho hello.asm && gcc -o hello hello.o
SECTION .rodata
hello.msg db 'Hello, World!',0x0a,0x00
SECTION .text
extern _printf ; could also use _puts...
GLOBAL _main
; aligns esp to 16 bytes in preparation for calling a C library function
; arg is number of bytes to pad for function arguments, this should be a multiple of 16
; unless you are using push/pop to load args
%macro clib_prolog 1
mov ebx, esp ; remember current esp
and esp, 0xFFFFFFF0 ; align to next 16 byte boundary (could be zero offset!)
sub esp, 12 ; skip ahead 12 so we can store original esp
push ebx ; store esp (16 bytes aligned again)
sub esp, %1 ; pad for arguments (make conditional?)
%endmacro
; arg must match most recent call to clib_prolog
%macro clib_epilog 1
add esp, %1 ; remove arg padding
pop ebx ; get original esp
mov esp, ebx ; restore
%endmacro
_main:
; set up stack frame
push ebp
mov ebp, esp
push ebx
clib_prolog 16
mov dword [esp], hello.msg
call _printf
; can make more clib calls here...
clib_epilog 16
; tear down stack frame
pop ebx
mov esp, ebp
pop ebp
mov eax, 0 ; set return code
ret
It is possible to recover it if Git hasn't garbage collected yet.
Get an overview of dangling commits with fsck:
$ git fsck --lost-found
dangling commit b72e67a9bb3f1fc1b64528bcce031af4f0d6fcbf
Recover the dangling commit with rebase:
$ git rebase b72e67a9bb3f1fc1b64528bcce031af4f0d6fcbf
James Sulak asked,
Is there any way I can make Python automatically print a ? instead of failing in this situation?
Other solutions recommend we attempt to modify the Windows environment or replace Python's print() function. The answer below comes closer to fulfilling Sulak's request.
Under Windows 7, Python 3.5 can be made to print Unicode without throwing a UnicodeEncodeError as follows:
In place of:
print(text)
substitute:
print(str(text).encode('utf-8'))
Instead of throwing an exception, Python now displays unprintable Unicode characters as \xNN hex codes, e.g.:
Halmalo n\xe2\x80\x99\xc3\xa9tait plus qu\xe2\x80\x99un point noir
Instead of
Halmalo n’était plus qu’un point noir
Granted, the latter is preferable ceteris paribus, but otherwise the former is completely accurate for diagnostic messages. Because it displays Unicode as literal byte values the former may also assist in diagnosing encode/decode problems.
Note: The str() call above is needed because otherwise encode() causes Python to reject a Unicode character as a tuple of numbers.
Object.keys does not return the right result in case of object inheritance. To properly count object properties, including inherited ones, use for-in. For example, by the following function (related question):
var objLength = (o,i=0) => { for(p in o) i++; return i }
var myObject = new Object();
myObject["firstname"] = "Gareth";
myObject["lastname"] = "Simpson";
myObject["age"] = 21;
var child = Object.create(myObject);
child["sex"] = "male";
var objLength = (o,i=0) => { for(p in o) i++; return i }
console.log("Object.keys(myObject):", Object.keys(myObject).length, "(OK)");
console.log("Object.keys(child) :", Object.keys(child).length, "(wrong)");
console.log("objLength(child) :", objLength(child), "(OK)");POST variables should be accessible via the request object: HttpRequest.getParameterMap(). The exception is if the form is sending multipart MIME data (the FORM has enctype="multipart/form-data"). In that case, you need to parse the byte stream with a MIME parser. You can write your own or use an existing one like the Apache Commons File Upload API.
I have been using Atlantis SQL Enywhere, a free software, for almost 6 months and has been working really well. Works with SQL 2005 and SQL 2008 versions. I am really impressed with its features and keyboard shortcuts are similar to VS, so makes the transition really smooth to a new editor.
Some of the features that are worth mentioning:
All these features have saved me lot of time.
I can think of 2 options
background-color for the column on the container <div/> instead (<div class="separator"/>) with repeat-yIshmaeel's answer generally does work, however I found one issue, which is that using OpenMappedMachineConfiguration seems to lose your inherited section groups from machine.config. This means that you can access your own custom sections (which is all the OP wanted), but not the normal system sections. For example, this code will not work:
ConfigurationFileMap fileMap = new ConfigurationFileMap(strConfigPath);
Configuration configuration = ConfigurationManager.OpenMappedMachineConfiguration(fileMap);
MailSettingsSectionGroup thisMail = configuration.GetSectionGroup("system.net/mailSettings") as MailSettingsSectionGroup; // returns null
Basically, if you put a watch on the configuration.SectionGroups, you'll see that system.net is not registered as a SectionGroup, so it's pretty much inaccessible via the normal channels.
There are two ways I found to work around this. The first, which I don't like, is to re-implement the system section groups by copying them from machine.config into your own web.config e.g.
<sectionGroup name="system.net" type="System.Net.Configuration.NetSectionGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<sectionGroup name="mailSettings" type="System.Net.Configuration.MailSettingsSectionGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<section name="smtp" type="System.Net.Configuration.SmtpSection, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
</sectionGroup>
</sectionGroup>
I'm not sure the web application itself will run correctly after that, but you can access the sectionGroups correctly.
The second solution it is instead to open your web.config as an EXE configuration, which is probably closer to its intended function anyway:
ExeConfigurationFileMap fileMap = new ExeConfigurationFileMap() { ExeConfigFilename = strConfigPath };
Configuration configuration = ConfigurationManager.OpenMappedExeConfiguration(fileMap, ConfigurationUserLevel.None);
MailSettingsSectionGroup thisMail = configuration.GetSectionGroup("system.net/mailSettings") as MailSettingsSectionGroup; // returns valid object!
I daresay none of the answers provided here, neither mine or Ishmaeel's, are quite using these functions how the .NET designers intended. But, this seems to work for me.
The most important part is the concepts. Once you understand how the building blocks work, differences in syntax amount to little more than mild dialects. A layer on top of your regular expression engine's syntax is the syntax of the programming language you're using. Languages such as Perl remove most of this complication, but you'll have to keep in mind other considerations if you're using regular expressions in a C program.
If you think of regular expressions as building blocks that you can mix and match as you please, it helps you learn how to write and debug your own patterns but also how to understand patterns written by others.
Conceptually, the simplest regular expressions are literal characters. The pattern N matches the character 'N'.
Regular expressions next to each other match sequences. For example, the pattern Nick matches the sequence 'N' followed by 'i' followed by 'c' followed by 'k'.
If you've ever used grep on Unix—even if only to search for ordinary looking strings—you've already been using regular expressions! (The re in grep refers to regular expressions.)
Adding just a little complexity, you can match either 'Nick' or 'nick' with the pattern [Nn]ick. The part in square brackets is a character class, which means it matches exactly one of the enclosed characters. You can also use ranges in character classes, so [a-c] matches either 'a' or 'b' or 'c'.
The pattern . is special: rather than matching a literal dot only, it matches any character†. It's the same conceptually as the really big character class [-.?+%$A-Za-z0-9...].
Think of character classes as menus: pick just one.
Using . can save you lots of typing, and there are other shortcuts for common patterns. Say you want to match a digit: one way to write that is [0-9]. Digits are a frequent match target, so you could instead use the shortcut \d. Others are \s (whitespace) and \w (word characters: alphanumerics or underscore).
The uppercased variants are their complements, so \S matches any non-whitespace character, for example.
From there, you can repeat parts of your pattern with quantifiers. For example, the pattern ab?c matches 'abc' or 'ac' because the ? quantifier makes the subpattern it modifies optional. Other quantifiers are
* (zero or more times)+ (one or more times){n} (exactly n times){n,} (at least n times){n,m} (at least n times but no more than m times)Putting some of these blocks together, the pattern [Nn]*ick matches all of
The first match demonstrates an important lesson: * always succeeds! Any pattern can match zero times.
A few other useful examples:
[0-9]+ (and its equivalent \d+) matches any non-negative integer\d{4}-\d{2}-\d{2} matches dates formatted like 2019-01-01A quantifier modifies the pattern to its immediate left. You might expect 0abc+0 to match '0abc0', '0abcabc0', and so forth, but the pattern immediately to the left of the plus quantifier is c. This means 0abc+0 matches '0abc0', '0abcc0', '0abccc0', and so on.
To match one or more sequences of 'abc' with zeros on the ends, use 0(abc)+0. The parentheses denote a subpattern that can be quantified as a unit. It's also common for regular expression engines to save or "capture" the portion of the input text that matches a parenthesized group. Extracting bits this way is much more flexible and less error-prone than counting indices and substr.
Earlier, we saw one way to match either 'Nick' or 'nick'. Another is with alternation as in Nick|nick. Remember that alternation includes everything to its left and everything to its right. Use grouping parentheses to limit the scope of |, e.g., (Nick|nick).
For another example, you could equivalently write [a-c] as a|b|c, but this is likely to be suboptimal because many implementations assume alternatives will have lengths greater than 1.
Although some characters match themselves, others have special meanings. The pattern \d+ doesn't match backslash followed by lowercase D followed by a plus sign: to get that, we'd use \\d\+. A backslash removes the special meaning from the following character.
Regular expression quantifiers are greedy. This means they match as much text as they possibly can while allowing the entire pattern to match successfully.
For example, say the input is
"Hello," she said, "How are you?"
You might expect ".+" to match only 'Hello,' and will then be surprised when you see that it matched from 'Hello' all the way through 'you?'.
To switch from greedy to what you might think of as cautious, add an extra ? to the quantifier. Now you understand how \((.+?)\), the example from your question works. It matches the sequence of a literal left-parenthesis, followed by one or more characters, and terminated by a right-parenthesis.
If your input is '(123) (456)', then the first capture will be '123'. Non-greedy quantifiers want to allow the rest of the pattern to start matching as soon as possible.
(As to your confusion, I don't know of any regular-expression dialect where ((.+?)) would do the same thing. I suspect something got lost in transmission somewhere along the way.)
Use the special pattern ^ to match only at the beginning of your input and $ to match only at the end. Making "bookends" with your patterns where you say, "I know what's at the front and back, but give me everything between" is a useful technique.
Say you want to match comments of the form
-- This is a comment --
you'd write ^--\s+(.+)\s+--$.
Regular expressions are recursive, so now that you understand these basic rules, you can combine them however you like.
†: The statement above that . matches any character is a simplification for pedagogical purposes that is not strictly true. Dot matches any character except newline, "\n", but in practice you rarely expect a pattern such as .+ to cross a newline boundary. Perl regexes have a /s switch and Java Pattern.DOTALL, for example, to make . match any character at all. For languages that don't have such a feature, you can use something like [\s\S] to match "any whitespace or any non-whitespace", in other words anything.
Don't forget the colours!
For some reason Delphi 7 in Twilight does not render Droid Sans Mono well, but in Visual Studio with an orange on black theme it is excellent. Deja Vu Sans Mono is the best all rounder. I use it almost everywhere. Consolas would be excellent apart from its ugly Q glyph.
One other thing I have found since I entered the world of work is that even though I have great eyesight I like to keep my code font around 12 or 13pt size both to reduce eye strain and to make sure I can't put too much text on screen. It's sort of an incentive to keep code blocks vertically short.
I note that this edit box does not respect my browser's default monospaced font. It's giving me Monaco (I'm on OSX). Monaco is horrible. It's glyphs have poorly angled elements and it's capitals are not well proportioned.
Oh, and it almost doesn't matter on Windows because your font will not look right anyway. /me dons flame retardent suit
The complete syntax depends on the database engine you're working with:
For SQL Server:
CASE case-expression
WHEN when-expression-1 THEN value-1
[ WHEN when-expression-n THEN value-n ... ]
[ ELSE else-value ]
END
or:
CASE
WHEN boolean-when-expression-1 THEN value-1
[ WHEN boolean-when-expression-n THEN value-n ... ]
[ ELSE else-value ]
END
expressions, etc:
case-expression - something that produces a value
when-expression-x - something that is compared against the case-expression
value-1 - the result of the CASE statement if:
the when-expression == case-expression
OR the boolean-when-expression == TRUE
boolean-when-exp.. - something that produces a TRUE/FALSE answer
Link: CASE (Transact-SQL)
Also note that the ordering of the WHEN statements is important. You can easily write multiple WHEN clauses that overlap, and the first one that matches is used.
Note: If no ELSE clause is specified, and no matching WHEN-condition is found, the value of the CASE expression will be NULL.
Well, those features are specific to a tool that you are using for development in those languages.
You wouldn't have those tools if (for example) you were using notepad to write code. So, maybe you should ask the question for the tool you are using.
For PHP: http://webservices.xml.com/pub/a/ws/2004/03/24/phpws.html
Quick answer : Add proxy configuration with parameter for both install/update
gem install --http-proxy http://host:port/ package_name
gem update --http-proxy http://host:port/ package_name
This will get you the tables in foreign key order and avoid dropping some of the tables created by SQL Server. The t.Ordinal value will slice the tables into dependency layers.
WITH TablesCTE(SchemaName, TableName, TableID, Ordinal) AS
(
SELECT OBJECT_SCHEMA_NAME(so.object_id) AS SchemaName,
OBJECT_NAME(so.object_id) AS TableName,
so.object_id AS TableID,
0 AS Ordinal
FROM sys.objects AS so
WHERE so.type = 'U'
AND so.is_ms_Shipped = 0
AND OBJECT_NAME(so.object_id)
LIKE 'MyPrefix%'
UNION ALL
SELECT OBJECT_SCHEMA_NAME(so.object_id) AS SchemaName,
OBJECT_NAME(so.object_id) AS TableName,
so.object_id AS TableID,
tt.Ordinal + 1 AS Ordinal
FROM sys.objects AS so
INNER JOIN sys.foreign_keys AS f
ON f.parent_object_id = so.object_id
AND f.parent_object_id != f.referenced_object_id
INNER JOIN TablesCTE AS tt
ON f.referenced_object_id = tt.TableID
WHERE so.type = 'U'
AND so.is_ms_Shipped = 0
AND OBJECT_NAME(so.object_id)
LIKE 'MyPrefix%'
)
SELECT DISTINCT t.Ordinal, t.SchemaName, t.TableName, t.TableID
FROM TablesCTE AS t
INNER JOIN
(
SELECT
itt.SchemaName AS SchemaName,
itt.TableName AS TableName,
itt.TableID AS TableID,
Max(itt.Ordinal) AS Ordinal
FROM TablesCTE AS itt
GROUP BY itt.SchemaName, itt.TableName, itt.TableID
) AS tt
ON t.TableID = tt.TableID
AND t.Ordinal = tt.Ordinal
ORDER BY t.Ordinal DESC, t.TableName ASC
Save the file. For this example, the file will be named C:\mysql-init.txt. it asking administrative permisions for saving the file
If you are going to include specific path in most of the files in your application, create a Global variable to your root folder.
define("APPLICATION_PATH", realpath(dirname(__FILE__) . '/../app'));
or
define("APPLICATION_PATH", realpath(DIR(__FILE__) . '/../app'));
Now this Global variable "APPLICATION_PATH" can be used to include all the files instead of calling realpath() everytime you include a new file.
EX:
include(APPLICATION_PATH ."/config/config.ini";
Hope it helps ;-)
One alternative would be a KeyedCollection if the key is embedded in the value.
Just create a basic implementation in a sealed class to use.
So to replace Dictionary<string, int> (which isn't a very good example as there isn't a clear key for a int).
private sealed class IntDictionary : KeyedCollection<string, int>
{
protected override string GetKeyForItem(int item)
{
// The example works better when the value contains the key. It falls down a bit for a dictionary of ints.
return item.ToString();
}
}
KeyedCollection<string, int> intCollection = new ClassThatContainsSealedImplementation.IntDictionary();
intCollection.Add(7);
int valueByIndex = intCollection[0];
If you're on ASP.NET MVC, you can try MVCMiniProfiler (http://benjii.me/2011/07/using-the-mvc-mini-profiler-with-entity-framework/)
In this case, IllegalArgumentException conveys clear information to the user using your API that the " should not be null". As other forum users pointed out you could use NPE if you want to as long as you convey the right information to the user using your API.
GaryF and tweakt dropped "Effective Java" (which I swear by) references which recommends using NPE. And looking at how other good APIs are constructed is the best way to see how to construct your API.
Another good example is to look at the Spring APIs. For example, org.springframework.beans.BeanUtils.instantiateClass(Constructor ctor, Object[] args) has a Assert.notNull(ctor, "Constructor must not be null") line. org.springframework.util.Assert.notNull(Object object, String message) method checks to see if the argument (object) passed in is null and if it is it throws a new IllegalArgumentException(message) which is then caught in the org.springframework.beans.BeanUtils.instantiateClass(...) method.
It depends on the number of images you are going to store and also their sizes. I have used databases to store images in the past and my experience has been fairly good.
IMO, Pros of using database to store images are,
A. You don't need FS structure to hold your images
B. Database indexes perform better than FS trees when more number of items are to be stored
C. Smartly tuned database perform good job at caching the query results
D. Backups are simple. It also works well if you have replication set up and content is delivered from a server near to user. In such cases, explicit synchronization is not required.
If your images are going to be small (say < 64k) and the storage engine of your db supports inline (in record) BLOBs, it improves performance further as no indirection is required (Locality of reference is achieved).
Storing images may be a bad idea when you are dealing with small number of huge sized images. Another problem with storing images in db is that, metadata like creation, modification dates must handled by your application.
The Microsoft AJAX library will accomplish this. You could also create your own solution that involves using AJAX to call your own aspx (as basically) script files to run .NET functions.
This is the library called AjaxPro which was written an MVP named Michael Schwarz. This was library was not written by Microsoft.
I have used AjaxPro extensively, and it is a very nice library, that I would recommend for simple callbacks to the server. It does function well with the Microsoft version of Ajax with no issues. However, I would note, with how easy Microsoft has made Ajax, I would only use it if really necessary. It takes a lot of JavaScript to do some really complicated functionality that you get from Microsoft by just dropping it into an update panel.
In Rails 3, you could do
$rails new projectname --database=mysql
I thought Sequel Pro for MySQL looked pretty interesting. It's hard to find one tool that works with all those databases (especially SQL Server 2005 . . . most people use SQL Server Management Studio and that's Windows only of course).
The question is old, yet I'd like to extend the topic with another answer.
My point is, the easiest way to achieve it is just to wrap multiple queries with a transaction. The accepted answer INSERT ... ON DUPLICATE KEY UPDATE is a nice hack, but one should be aware of its drawbacks and limitations:
"Field 'fieldname' doesn't have a default value" MySQL warning even if you don't insert a single row at all. It will get you into trouble, if you decide to be strict and turn mysql warnings into runtime exceptions in your app.I made some performance tests for three of suggested variants, including the INSERT ... ON DUPLICATE KEY UPDATE variant, a variant with "case / when / then" clause and a naive approach with transaction. You may get the python code and results here. The overall conclusion is that the variant with case statement turns out to be twice as fast as two other variants, but it's quite hard to write correct and injection-safe code for it, so I personally stick to the simplest approach: using transactions.
Edit: Findings of Dakusan prove that my performance estimations are not quite valid. Please see this answer for another, more elaborate research.
No you cannot get the MAC address in JavaScript, mainly because the MAC address uniquely identifies the running computer so it would be a security vulnerability.
Now if all you need is a unique identifier, I suggest you create one yourself using some cryptographic algorithm and store it in a cookie.
If you really need to know the MAC address of the computer AND you are developing for internal applications, then I suggest you use an external component to do that: ActiveX for IE, XPCOM for Firefox (installed as an extension).
Even if you capture the keydown/keyup event, those are the only events that the tab key fires, you still need some way to prevent the default action, moving to the next item in the tab order, from occurring.
In Firefox you can call the preventDefault() method on the event object passed to your event handler. In IE, you have to return false from the event handle. The JQuery library provides a preventDefault method on its event object that works in IE and FF.
<body>
<input type="text" id="myInput">
<script type="text/javascript">
var myInput = document.getElementById("myInput");
if(myInput.addEventListener ) {
myInput.addEventListener('keydown',this.keyHandler,false);
} else if(myInput.attachEvent ) {
myInput.attachEvent('onkeydown',this.keyHandler); /* damn IE hack */
}
function keyHandler(e) {
var TABKEY = 9;
if(e.keyCode == TABKEY) {
this.value += " ";
if(e.preventDefault) {
e.preventDefault();
}
return false;
}
}
</script>
</body>
You can use:
<script type="text/javascript">
Window.body.style.backgroundColor = "#5a5a5a";
</script>
Static methods are not instantiated as such, they're just available without an object reference.
A call to a static method is done through the class name, not through an object reference, and the Intermediate Language (IL) code to call it will call the abstract method through the name of the class that defined it, not necessarily the name of the class you used.
Let me show an example.
With the following code:
public class A
{
public static void Test()
{
}
}
public class B : A
{
}
If you call B.Test, like this:
class Program
{
static void Main(string[] args)
{
B.Test();
}
}
Then the actual code inside the Main method is as follows:
.entrypoint
.maxstack 8
L0000: nop
L0001: call void ConsoleApplication1.A::Test()
L0006: nop
L0007: ret
As you can see, the call is made to A.Test, because it was the A class that defined it, and not to B.Test, even though you can write the code that way.
If you had class types, like in Delphi, where you can make a variable referring to a type and not an object, you would have more use for virtual and thus abstract static methods (and also constructors), but they aren't available and thus static calls are non-virtual in .NET.
I realize that the IL designers could allow the code to be compiled to call B.Test, and resolve the call at runtime, but it still wouldn't be virtual, as you would still have to write some kind of class name there.
Virtual methods, and thus abstract ones, are only useful when you're using a variable which, at runtime, can contain many different types of objects, and you thus want to call the right method for the current object you have in the variable. With static methods you need to go through a class name anyway, so the exact method to call is known at compile time because it can't and won't change.
Thus, virtual/abstract static methods are not available in .NET.
Don't forget to also allow for space complexities that can also be a cause for concern if one has limited memory resources. So for example you may hear someone wanting a constant space algorithm which is basically a way of saying that the amount of space taken by the algorithm doesn't depend on any factors inside the code.
Sometimes the complexity can come from how many times is something called, how often is a loop executed, how often is memory allocated, and so on is another part to answer this question.
Lastly, big O can be used for worst case, best case, and amortization cases where generally it is the worst case that is used for describing how bad an algorithm may be.
Use real world analogy and imaginary characters to teach them programming. Like when I teach people about variables and control statements etc.
Usually I start with calculator example. I say imagine u have a box for every variable and u have 10 card boards with numbers 0 - 9 printed on them. Say that the box can hold one cardboard at a time and similar ways to explain how programming elements work
And emphasis on how every operator works.. like the simple '=' operator always computes the right hand side first into one value. and put that value into box named "num_1" (which is variable name)
This has been very very effective, as they are able to imagine the flow very quickly.
For what it's worth, if you needed to pass the function (or class) name and app name as a string, then you could do this:
myFnName = "MyFn"
myAppName = "MyApp"
app = sys.modules[myAppName]
fn = getattr(app,myFnName)
Before using Inversion of Control you should be well aware of the fact that it has its pros and cons and you should know why you use it if you do so.
Pros:
Cons:
Personally I see the strong points of IoC and I really like them but I tend to avoid IoC whenever possible because it turns your software into a collection of classes that no longer constitute a "real" program but just something that needs to be put together by XML configuration or annotation metadata and would fall (and falls) apart without it.
I always use method 2 as well. The only benefit of using each is if you're just reading (rather than re-assigning) the value of the hash entry, you're not constantly de-referencing the hash.
I have created a recursive function to concatenate a list of strings with a separator between them. I use it mostly to create SQL expressions, by passing a list of fields as the 'items' and a 'comma+space' as the separator. Here's the function (It uses some Borland Builder native data types, but can be adapted to fit any other environment):
String ArrangeString(TStringList* items, int position, String separator)
{
String result;
result = items->Strings[position];
if (position <= items->Count)
result += separator + ArrangeString(items, position + 1, separator);
return result;
}
I call it this way:
String columnsList;
columnsList = ArrangeString(columns, 0, ", ");
Imagine you have an array named 'fields' with this data inside it: 'albumName', 'releaseDate', 'labelId'. Then you call the function:
ArrangeString(fields, 0, ", ");
As the function starts to work, the variable 'result' receives the value of the position 0 of the array, which is 'albumName'.
Then it checks if the position it's dealing with is the last one. As it isn't, then it concatenates the result with the separator and the result of a function, which, oh God, is this same function. But this time, check it out, it call itself adding 1 to the position.
ArrangeString(fields, 1, ", ");
It keeps repeating, creating a LIFO pile, until it reaches a point where the position being dealt with IS the last one, so the function returns only the item on that position on the list, not concatenating anymore. Then the pile is concatenated backwards.
Got it? If you don't, I have another way to explain it. :o)
Visual Studio also has a feature that will generate a Property from a private variable.
If you right-click on a variable, in the context menu that pops up, click on the "Refactor" item, and then choose Encapsulate Field.... This will create a getter/setter property for a variable.
I'm not too big a fan of this technique as it is a little bit awkward to use if you have to create a lot of getters/setters, and it puts the property directly below the private field, which bugs me, because I usually have all of my private fields grouped together, and this Visual Studio feature breaks my class' formatting.