Modify array with Array.Foreach and lambda expression

Question

I'm trying to modify the values of the array but it doesn't get modified:

string buzones = File.ReadAllText("c:\\Buzones");
string[] buzoneslist = buzones.Split(',');
Array.ForEach(buzoneslist, x =>
{
 x = x.Replace(",", "");
});

It's like I'm doing a string.Replace without setting the resultant value to the variable:

s.replace(",", ""); instead of s=s.replace(",", "");

Is it possible to accomplish inside a lambda expression?.

• leppie: No, and it never will. Also, horrible style. Use Select instead and create a new array.

Answer 1

No, you can't modify an array while you're enumerating it with ForEach, and strings are immutable so there's no function that will modify the instance in-place.

You could do either:

for (int i=0; i<buzoneslist.Length; i++) 
 buzoneslist[i] = buzoneslist[i].Replace(",", "");

Or:

buzoneslist = buzoneslist.Select(t => t.Replace(",", "")).ToArray();

I suppose if you really wanted to use a lambda, you could write an extension method:

public static class Extensions {
 public static void ChangeEach<T>(this T[] array, Func<T,T> mutator) {
 for (int i=0; i<array.Length; i++) {
 array[i] = mutator(array[i]);
 }
 }
}

And then:

buzoneslist.ChangeEach(t => t.Replace(",", ""));