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  1. #1
    nemo is offline Member
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    May 2007
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    Default How to determine if the value of a JTextField is double

    I have a textfield and i want it to have only double values. How can i make sure of this?

  2. #2
    levent Guest

    Default

    Double has parseDouble method which tries to parse a String as a Double. You need to put it inside a try-catch block since it throws NumberFormatException.

    You can write logic inside catch since it is called if the value is not a valid double!

    Here is an example code:

    Java Code:
    double value;
    
    try {
      // String textValue = the string from your JTextField
      value = Double.parseDouble(textValue);
      // if the code gets to here, it was recognizable as a double
    }
    catch(NumberFormatException e) {
      // if the code gets to here, it was NOT recognizable as a double
    }

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