I have form field where user has to input the number.

Questions:

1) How to check if user inputed a number?
2) Is there any function in javascript to check if string is numeric?

Thank you

function CheckPhoneNumber(TheNumber) {
var valid = 1
var GoodChars = "0123456789()-+ "
var i = 0
if (TheNumber=="") {
// Return false if number is empty
valid = 0
}
for (i =0; i <= TheNumber.length -1; i++) {
if (GoodChars.indexOf(TheNumber.charAt(i)) == -1) {
// Note: Remove the comments from the following line to see this
// for loop in action.
// alert(TheNumber.charAt(i) + " is no good.")
valid = 0
} // End if statement
} // End for loop
return valid
}



Source (http://webdeveloper.com/javascript/javascript_form_verification_2.html)

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