Check for value in list

I've got a generic list of values. I want to check to see if an Id exists in that generic list.

What's the easiest way to go about this?

example

List<someCustomObject> mylist = GetCustomObjectList();

int idToCheckFor = 12;

I want to see if 12 exists in any of the custom objects in the list by checking each someCustomObject.Id = idToCheckFor

If a match is found, I'm good to go and my method will return a bool true. I'm just trying to figure out if there's an easy way instead of looping through each item in the list to see if idToCheckFor == someCustomObject.id and setting a variable to true if a match 开发者_开发技巧is found. I'm sure there's got to be a better way to go about this.

If you're using .NET 3.5, this is easy using LINQ to objects:

return myList.Any(o => o.ID == idToCheckFor);

Aside from that, looping through is really your only option.

Boolean b = myList.Find(obj => obj.id == 12) != null;

LINQ makes life easier

mylist.Where(x => x.id == idToCheckFor).Any()

Thanks

 bool found = mylist.Any(p => p.Id == idToCheckFor);

bool bExists = myList.Any(x=>x.id == idToCheckFor);

if(mylist.Any(Item => Item.Id == idToCheckFor))
{
  do();
}

I think you are using the wrong data structure for this. What you need is:

Dictionary<int, someCustomObject> myDictionary = GetCustomObjectDictionary();

Now you can easily check if the ID exists with fantastic performance.

return myDictionary.ContainsKey(idToCheckFor);

return myList.Exists(item => item.Id == idToCheckFor);

For linq resources you can check 101 linq samples

Use LINQ to Objects. Something like the following:

var result = from l in mylist
             where l.id = 12
             select l;

return result != null;