change array size

user522860 picture user522860 · Jan 30, 2011 · Viewed 185.8k times · Source

Is it possible to change an array size after declaration? If not, is there any alternative to arrays?
I do not want to create an array with a size of 1000, but I do not know the size of the array when I'm creating it.

Answer

Chris Shain picture Chris Shain · Jan 30, 2011

You can use Array.Resize(), documented in MSDN.

But yeah, I agree with Corey, if you need a dynamically sized data structure, we have Lists for that.

Important: Array.Resize() doesn't resize the array (the method name is misleading), it creates a new array and only replaces the reference you passed to the method.

An example:

var array1 = new byte[10];
var array2 = array1;
Array.Resize<byte>(ref array1, 20);

// Now:
// array1.Length is 20
// array2.Length is 10
// Two different arrays.