Create File If File Does Not Exist

Question

I need to get my code to read if file doesnt exist create else append  Right now it is reading if it does exist create and append  Here is the code   if  File Exists path         using  StreamWriter sw   File CreateText path           Would I do this   if    File Exists path         using  StreamWriter sw   File CreateText path           Edit   string path   txtFilePath Text   if   File Exists path         using  StreamWriter sw   File CreateText path                 foreach  var line in employeeList Items                        sw WriteLine   Employee line  FirstName               sw WriteLine   Employee line  LastName               sw WriteLine   Employee line  JobTitle                     else       StreamWriter sw   File AppendText path        foreach  var line in employeeList Items                sw WriteLine   Employee line  FirstName           sw WriteLine   Employee line  LastName           sw WriteLine   Employee line  JobTitle             sw Close

User · Answer

This works as well for me  string path   TextFile     txt    if   File Exists HttpContext Current Server MapPath path          File Create HttpContext Current Server MapPath path   Close      using  StreamWriter w   File AppendText HttpContext Current Server MapPath path          w WriteLine   0     Hello World        w Flush        w Close

User · Answer

You can simply call   using  StreamWriter w   File AppendText  log txt      It will create the file if it doesn t exist and open the file for appending   Edit   This is sufficient   string path   txtFilePath Text                 using StreamWriter sw   File AppendText path       foreach  var line in employeeList Items                                               Employee e    Employee line     unbox once     sw WriteLine e FirstName                            sw WriteLine e LastName                            sw WriteLine e JobTitle                                 But if you insist on checking first  you can do something like this  but I don t see the point     string path   txtFilePath Text                   using  StreamWriter sw    File Exists path     File AppendText path    File CreateText path                                                foreach  var line in employeeList Items                                                            sw WriteLine   Employee line  FirstName                                  sw WriteLine   Employee line  LastName                                  sw WriteLine   Employee line  JobTitle                                                     Also  one thing to point out with your code is that you re doing a lot of unnecessary unboxing   If you have to use a plain  non-generic  collection like ArrayList  then unbox the object once and use the reference   However  I perfer to use List lt  gt  for my collections   public class EmployeeList   List lt Employee gt

User · Answer

You don t even need to do the check manually  File Open does it for you  Try   using  StreamWriter sw   new StreamWriter File Open path  System IO FileMode Append         Ref  http   msdn microsoft com en-us library system io filemode aspx

User · Answer

For Example      string rootPath   Path GetPathRoot Environment GetFolderPath Environment SpecialFolder System            rootPath     MTN           if    File Exists rootPath                          File CreateText rootPath

User · Answer

private List lt Url gt  AddURLToFile Urls urls  Url url        string filePath     D  test file json       urls UrlList Add url          if   System IO File Exists filePath             using  System IO File Delete filePath         System IO File WriteAllText filePath  JsonConvert SerializeObject urls UrlList           using  StreamWriter sw    System IO File Exists filePath     System IO File AppendText filePath    System IO File CreateText filePath                     sw WriteLine JsonConvert SerializeObject urls UrlList                return urls UrlList     private List lt Url gt  ReadURLToFile             string filePath   Path Combine Path GetDirectoryName Assembly GetExecutingAssembly   Location     App Data file json        string filePath     D  test file json        List lt Url gt  result   new List lt Url gt           if   System IO File Exists filePath           using  System IO File CreateText filePath            using  StreamReader file   new StreamReader filePath                 result   JsonConvert DeserializeObject lt List lt Url gt  gt  file ReadToEnd             file Close              if  result    null          result   new List lt Url gt          return result

User · Answer

Yes  you need to negate File Exists path  if you want to check if the file doesn t exist

User · Answer

This will enable appending to file using StreamWriter  using  StreamWriter stream   new StreamWriter  quot YourFilePath quot   true          This is default mode  not append to file and create a new file  using  StreamWriter stream   new StreamWriter  quot YourFilePath quot   false                                   or using  StreamWriter stream   new StreamWriter  quot YourFilePath quot          Anyhow if you want to check if the file exists and then do other things you can use using  StreamWriter sw    File Exists path     File AppendText path    File CreateText path

User · Answer

or  using FileStream fileStream   File Open path  FileMode Append   using StreamWriter file   new StreamWriter fileStream

[c#] Create File If File Does Not Exist

Examples related to c#

Examples related to streamwriter