how to remove from list using Lambda syntax

问题:

Given:

List<Name> names = new List<Name>(); //list full of names

public void RemoveName(string name) {
   List<Name> n = names.Where(x => x.UserName == name);;
   names.Remove(n);
}

What's the Lambda syntax to execute the removal?

And how can I get indication of "success" if the function did remove or not?

回答1:

names.RemoveAll(x => x.UserName == name);

Note here that all the lambda syntax does is provide a Predicate<T>; lambda syntax is entirely unrelated to what it ends up doing with the lambda.

Or for a single match (see comments):

var found = names.Find(x => x.UserName == name);
if(found != null) names.Remove(found);

or:

var index = names.FindIndex(x => x.UserName == name);
if(index >= 0) names.RemoveAt(index);

回答2:

var n = names.SingleOrDefault(x => x.UserName == name)
if(n != null && n.UserName.length > 0)
{
 names.Remove(n);
}

OR

var n= names.Where(x => x.UserName == name).First();
names.Remove(n)