Textfield doubt, multiplayer purpose...

hi everyone, ive already searched like a half day and i got nothing…
my question is:

How can i make my textfield to detect only text… Not numbers or other signs, just that, text… and how can i make a system to detect if the username putted in the field is already taken or not? or can you point me in the right direction to do that?

thanks a lot in advance :smiley:

---------- EDIT-

var namefield: String;
var newSkin: GUISkin; 

function OnGUI(){
	GUI.skin = newSkin;
	namefield = GUI.TextField(Rect(Screen.width/2.01,Screen.height*0.85,Screen.width/3.62,Screen.height/15.7), namefield, 10);
	
}

this is the code that i have by now

To remove all non-alpha characters you could do this:

namefield = GUI.TextField(...., namefield);
namefield = Regex.Replace(namefield, "^[a-zA-Z]", "");

Remember to add the correct using statement for the Regex class also:

using System.Text.RegularExpressions;

in java?