Replace an specific kind of chars

replacechar

/**
 * REPLACE ALL CHARS
 * (but the name is not.... i know!)
 */

String.prototype.replaceChar=function(position, char) {
	return this.substr(0, position) + char + this.substr(position, this.length);
}

String.prototype.replaceAllChars = function(thisChar, forThisChar){
	var lngChar = forThisChar.length;
	var _tmp = this;
	for (var position=0; position < _tmp.length; position++){
		if(_tmp[position] == thisChar){
			_tmp = _tmp.replaceChar(position, forThisChar);
			position = position+(lngChar+1);
		}
	}
	return _tmp;
}