How I can make a string equal to a textfield?

I have a TextField which I want to write something on it, and that can be copied what you wrote in a string.Please help me.

thanks in advance

you should do somthing like this:

var stringToEdit = "Hello World";
var finalString : String;
function OnGUI () {
    // Make a text field that modifies stringToEdit.
    stringToEdit = GUI.TextField (Rect (10, 10, 200, 20), stringToEdit, 25);
    if (GUI.Button(Rect(0,0,50,50),"CopyText"))
       finalString = stringToEdit;