Validation of a input number using Java script

[Deepak Sahu]

Hi All ,

Please someone provide the javascript code for validation of a input number .


Conditions -

If we input like 0005 ,it should throw error ,but if we input 5 it should not throw any error (It means zeroes are not allowed before any number) .


If we input 0,it should not throw any error (Single zero is allowed ).

[Eric Pascarello]

function isANumber( str ){
   var num = parseFloat(str);
   return !isNaN(num) && str.toString().match(/^00/)===null;
}

console.log("0\t: " + isANumber("0"));
console.log("00005\t: " + isANumber("00005"));
console.log("0.00123\t :" + isANumber("0.00123"));

Eric