Nodejs Utililty Methods String Starts With

String.prototype.startsWith = function(prefix) {
  return this.slice(0, str.length) == str;
};

String.prototype.startsWith = function(prefix){
    return (this.lastIndexOf(prefix, 0) === 0);
};

'use strict';
var mime = require('mime');
String.prototype.startsWith = function(prefix) {
  return this.indexOf(prefix) === 0;
};
String.prototype.endsWith = function(suffix) {
  return this.indexOf(suffix, this.length - suffix.length) !== -1;
};

String.prototype.startsWith = function (prefix){
  return this.slice(0, prefix.length) == prefix;

String.prototype.startsWith = function(prefix)
  if(prefix == null)
    return false;
  if(this.length < prefix.length)
    return false;
  return this.substring(0, prefix.length) == prefix;
};
String.prototype.endsWith = function(suffix)
...

String.prototype.startsWith = function (prefix) {
  return this.substring(0, prefix.length) == prefix;
};

String.prototype.startsWith = function (prefix, ignoreCase) {
    var _prefix = prefix.source ? prefix.source : prefix.escapeRegExp();
    return this.match(new RegExp("^" + _prefix, ignoreCase ? 'i' : ''));
};
String.prototype.endsWith = function (suffix, ignoreCase) {
    var _suffix = suffix.source ? suffix.source : suffix.escapeRegExp();
    return this.match(new RegExp(_suffix + "$", ignoreCase ? 'i' : ''));
};
String.prototype.escapeRegExp = function() {
...

String.prototype.startsWith = function (s) {
    if (this.substr(0, s.length) === s)
        return true;
    else
        return false;

String.prototype.startsWith = function (s) {
  return (this.indexOf(s) === 0);

String.prototype.startsWith = function(s) {
    return (s === this.substr(0, s.length));