Errors: Deprecated String generics

信息

Warning: Warning: String.charCodeAt Warning: String.concat Warning: String.contains Warning: String.endsWith Warning: String.includes Warning: String.indexOf Warning: String.lastIndexOf Warning: String.localeCompare Warning: String.match Warning: String.normalize Warning: String.replace Warning: String.search Warning: String.slice Warning: String.split Warning: String.startsWith Warning: String.substr Warning: String.substring Warning: String.toLocaleLowerCase Warning: String.toLocaleUpperCase Warning: String.toLowerCase Warning: String.toUpperCase Warning: String.trim Warning: String.trimLeft Warning: String.trimRight

String.charAt            is deprecated; use String.prototype.charAt            instead is deprecated; use String.prototype.charCodeAt        instead is deprecated; use String.prototype.concat            instead is deprecated; use String.prototype.contains          instead is deprecated; use String.prototype.endsWith          instead is deprecated; use String.prototype.includes          instead is deprecated; use String.prototype.indexOf           instead is deprecated; use String.prototype.lastIndexOf       instead is deprecated; use String.prototype.localeCompare     instead is deprecated; use String.prototype.match             instead is deprecated; use String.prototype.normalize         instead is deprecated; use String.prototype.replace           instead is deprecated; use String.prototype.search            instead is deprecated; use String.prototype.slice             instead is deprecated; use String.prototype.split             instead is deprecated; use String.prototype.startsWith        instead is deprecated; use String.prototype.substr            instead is deprecated; use String.prototype.substring         instead is deprecated; use String.prototype.toLocaleLowerCase instead is deprecated; use String.prototype.toLocaleUpperCase instead is deprecated; use String.prototype.toLowerCase       instead is deprecated; use String.prototype.toUpperCase       instead is deprecated; use String.prototype.trim              instead is deprecated; use String.prototype.trimLeft          instead is deprecated; use String.prototype.trimRight         instead

错误类型

警告。JavaScript执行不会停止。

什么地方出了错？

非标准的泛型String方法已被弃用，将来将被删除（不支持跨浏览器，仅在Firefox中可用）。字符串泛型String在String对象上提供实例方法，允许将String方法应用于任何对象。

Firefox bug 1222552跟踪String泛型方法的删除。

例子

弃用的语法

var num = 15; 
String.replace(num, /5/, '2'

标准语法

var num = 15;
String(num).replace(/5/, '2'

Shim

以下是对不支持的浏览器提供支持的一个补充：

/*globals define*/
// Assumes all supplied String instance methods already present
// (one may use shims for these if not available)
(function() {
  'use strict';

  var i,
    // We could also build the array of methods with the following, but the
    //   getOwnPropertyNames() method is non-shimable:
    // Object.getOwnPropertyNames(String).filter(function(methodName) {
    //   return typeof String[methodName] === 'function';
    // }
    methods = [
      'contains', 'substring', 'toLowerCase', 'toUpperCase', 'charAt',
      'charCodeAt', 'indexOf', 'lastIndexOf', 'startsWith', 'endsWith',
      'trim', 'trimLeft', 'trimRight', 'toLocaleLowerCase', 'normalize',
      'toLocaleUpperCase', 'localeCompare', 'match', 'search', 'slice',
      'replace', 'split', 'substr', 'concat', 'localeCompare'
    ],
    methodCount = methods.length,
    assignStringGeneric = function(methodName) {
      var method = String.prototype[methodName];
      String[methodName] = function(arg1) {
        return method.apply(arg1, Array.prototype.slice.call(arguments, 1)
      };
    };

  for (i = 0; i < methodCount; i++) {
    assignStringGeneric(methods[i]
  }
}()