I'm new to C# ASP.NET, and am working on my first application.
I'm trying to create a linq statment that return an arrary.
I have a table of products. I want to be able to select name, id, and price, for each product where the status == 1.
I am struggling with crating a way to do this. I have only been able to return individual items/columns. I have been stuck on this wayyy to long.
This is what I have so far:
try
{
using (UserDataDataContext db = new UserDataDataContext())
{
return db.mrobProducts.Select(x => x.Name).OrderBy(x => x).ToArray();
}
}
If you look in the screen shot below, you can see I have 2 errors, Select = Type object can not be refered from it's usage ToArray = cant resolve symbol to array
The answer is
Not sure what you table structure is like but see below.
public NamePriceModel[] AllProducts()
{
try
{
using (UserDataDataContext db = new UserDataDataContext())
{
return db.mrobProducts
.Where(x => x.Status == 1)
.Select(x => new NamePriceModel {
Name = x.Name,
Id = x.Id,
Price = x.Price
})
.OrderBy(x => x.Id)
.ToArray();
}
}
catch
{
return null;
}
}
This would return an array of type anonymous with the members you require.
Update:
Create a new class.
public class NamePriceModel
{
public string Name {get; set;}
public decimal? Price {get; set;}
public int Id {get; set;}
}
I've modified the query above to return this as well and you should change your method from returning string[] to returning NamePriceModel[].
Object AccountObject = _dbContext.Accounts
.Join(_dbContext.Users, acc => acc.AccountId, usr => usr.AccountId, (acc, usr) => new { acc, usr })
.Where(x => x.usr.EmailAddress == key1)
.Where(x => x.usr.Hash == key2)
.Select(x => new { AccountId = x.acc.AccountId, Name = x.acc.Name })
.SingleOrDefault();
using LINQ and Lamba, i wanted to return two field values and assign it to single entity object field;
as Name = Fname + " " + LName;
See my below code which is working as expected; hope this is useful;
Myentity objMyEntity = new Myentity
{
id = obj.Id,
Name = contxt.Vendors.Where(v => v.PQS_ID == obj.Id).Select(v=> new { contact = v.Fname + " " + v.LName}).Single().contact
}
no need to declare the 'contact'
You can use:
public YourClass[] AllProducts()
{
try
{
using (UserDataDataContext db = new UserDataDataContext())
{
return db.mrobProducts.Where(x => x.Status == 1)
.OrderBy(x => x.ID)
.Select(x => new YourClass { ID = x.ID, Name = x.Name, Price = x.Price})
.ToArray();
}
}
catch
{
return null;
}
}
And here is YourClass implementation:
public class YourClass
{
public string Name {get; set;}
public int ID {get; set;}
public int Price {get; set;}
}
And your AllProducts method's return type must be YourClass[].
Source: Stackoverflow.com