How to check the value entered in EditText is aplhanumeric or not?

Question

My application takes userid from user as input, the userid is alphanumeric i.e just the first character is (a-z), other part is numeric. How can I validate input of this type ( like G34555) ?

Answer 1

Use a regex. This should do it assuming the first letter can be upper or lower case:

 Pattern p = Pattern.compile("[a-zA-Z][0-9]+");

 Matcher m = p.matcher("some text you want");
 boolean isAlphaNum = m.matches();

Answer 2

I have resolved issue by using simple string function matches

String str="mystring";

str.matches("[a-zA-Z][0-9]+");

Answer 3

http://osdir.com/ml/Android-Developers/2009-11/msg02501.html seems like a more decent solution, it does not allow entering the chars that are not accepted.