How to convert integer to string and string to integer?

[Mindy Wu]

I know a method to convert string to interger:
for example:
String strNum = "123";
int intNum = Integer.parseInt(strNum);
Is there are any other way to do the same thing?? By the way, how to use toString(); when should I include argument in the () and don't.
Mindy Wu

[Art Metzer]

Hi, Mindy.
If you decide to go with your code, remember that parseInt() throws a NumberFormatException.
You could also use

public class StringToInt {
    public static void main( String[] args ) {
        String s = "123";
        int i = Integer.valueOf( s ).intValue();
        System.out.println( i );
    }
}

To convert an int to a String, use any one of the following:

String s = String.valueOf(i);
String s = Integer.toString(i);
String s = Integer.toString(i, radix);
// briefer but may result in extra object allocation.
String s = "" + i;

(This information from the Java FAQ.)
And, to my knowledge, the toString() method never takes any arguments. To use it, just call it from whatever object you'd like to see in string form: Integer.toString(), Object.toString(), etc. The resultant object will of course be a String.
Hope this helps, Mindy.
Art

[Bosun Bello]

You may want to look up the intValue() method. To convert in int to a string object, You can just wrap your in value using the Integer() method.
Bosun

[Mindy Wu]

Thank you all! That's really help me out!

Happy programmer!
Mindy