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How do I use the Find method on a generic List collection

Hello!

Assume I have the class shown below and it's stored in a generic List.
If I want to find the Value for a specific Id how do I use the find method.
We can assume that the generic List collection is named
myWorkSheetRowP arameterList

public class WorkSheetRowPar ameter
{
public string WorkSheetRowId {get; set};
public string Id {get;set};l
public string Type {get;set};
public string Value {get;set};
public string Disabled{get;se t};
public string ParameterName{g et;set};
public string ParameterDuplic ate{get;set};
}

//Tony
Sep 22 '08 #1
3 2175
You need a "predicate" - i.e. a condition to match, expressed as a
delegate. Since you are using C# 3.0, this is simply:

string id = "abc"; // etc
WorkSheetRowPar ameter row =
myWorkSheetRowP arameterList.Fi nd(
x =x.Id == id);

Marc
Sep 22 '08 #2
oh, I forgot - you'll need to get .Value afterwards.

Actually, with LINQ (in .NET 3.5) you can also do:

string id = "abc"; // etc
string value = (from row in myWorkSheetRowP arameterList
where row.Id == id
select row.Value).Sing le();

Marc
Sep 22 '08 #3
Tony Johansson <t.*********@lo gica.comwrote:
Assume I have the class shown below and it's stored in a generic List.
If I want to find the Value for a specific Id how do I use the find method.
We can assume that the generic List collection is named
myWorkSheetRowP arameterList

public class WorkSheetRowPar ameter
{
public string WorkSheetRowId {get; set};
public string Id {get;set};l
public string Type {get;set};
public string Value {get;set};
public string Disabled{get;se t};
public string ParameterName{g et;set};
public string ParameterDuplic ate{get;set};
}
It looks like you're using C# 3, so use a lambda expression:

string id = // the ID you want to find.
var found = myWorkSheetRowP arameterList.Fi nd(p =p.Id == id);
string value = found.Value;

--
Jon Skeet - <sk***@pobox.co m>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon.skeet
C# in Depth: http://csharpindepth.com
Sep 22 '08 #4

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