Javascript String digit()

/*/*w  ww  .  j  a  v  a  2 s .co  m*/
Implement String#digit? (in Java StringUtils.isDigit(String)), which should return true if given object is a digit (0-9), false otherwise.
*/

String.prototype.digit = function() {
  return /^\d$/i.test(this);
};

//Implement String#digit? (in Java StringUtils.isDigit(String)), 
//which should return true if given object is a digit (0-9), false otherwise.

String.prototype.digit = function() {
  return this.match(/^[0-9]$/) ? true : false;
};

String.prototype.digit = function() {
  
var reg = new RegExp('^[0-9]$');
console.log(this,reg);/*from w w  w  .  j av  a 2  s . co  m*/
return reg.test(this);
  
};

String.prototype.digit = function () {
    return /^\d$/.test(this) && this < 10;
};

console.log("2".digit());

String.prototype.digit = function() {
  if (this.length!=1) return false;
  if (this[0]>='0'&&this[0]<='9') 
    return true;//from   w  w w  .  j  a v a2s. co m
  else
    return false;
};

/*/*from   w w  w  .  j  a v a 2  s  .  c  om*/
Description:

Implement String#digit? (in Java StringUtils.isDigit(String)), 
which should return true if given object is a digit (0-9), false otherwise.
*/

String.prototype.digit = function() {  
 return /^\d$/g.test(this);
};

String.prototype.digit = function() {
  return /^\d$/.test(this);
};

// mine is below/*  ww w.  ja v a  2  s  .  c om*/


String.prototype.digit = function() {
  if (/[a-z\s]/gi.test(this)) return false;
  if (this>9) return false;
  return /[0-9]/g.test(this);
};

''.digit() // , false);
'7'.digit() // , true);
' '.digit() //, false);
'14'.digit() //, false);

console.clear();//from   ww  w  .j  av a2s  .  c om

/*
-----------------------------------------
8 kyu
Regexp Basics - is it a digit?
-----------------------------------------

Create a string constructor method called digit that 
should return true if given object is a digit (0-9), false otherwise.
*/
// --------------------------------------
String.prototype.digit = function() {
  return /^\d$/.test(this);
};

var size = '9'
console.log(  size.digit()  );



// --------------------------------------
String.prototype.digit2 = function() {
  return /^[0-9]$/.test(this);
};
// you can add global flag like this return /^\d$/g.test(this);