search()
方法执行正则表达式和 String
对象之间的一个搜索匹配。
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.
语法
str.search(regexp)
参数
-
regexp
-
一个
正则表达式(regular expression)
对象。如果传入一个非正则表达式对象obj
,则会使用new RegExp(obj)
隐式地将其转换为正则表达式对象。
返回值
如果匹配成功,则 search()
返回正则表达式在字符串中首次匹配项的索引;否则,返回 -1。
描述
当你想要知道字符串中是否存在某个模式(pattern)时可使用 search()
,类似于正则表达式的 exec()
方法。
示例
例子:使用 search()
下面的例子中用两个不同的正则表达式对同一个字符串执行搜索匹配,得到一个成功匹配(正数返回值)和一个失败匹配(-1)。
var str = "hey JudE"; var re = /[A-Z]/g; var re2 = /[.]/g; console.log(str.search(re)); // returns 4, which is the index of the first capital letter "J" console.log(str.search(re2)); // returns -1 cannot find '.' dot punctuation
规范
规范 | 状态 | 备注 |
---|---|---|
ECMAScript 3rd Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.2. |
ECMAScript 5.1 (ECMA-262) String.prototype.search |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) String.prototype.search |
Standard | |
ECMAScript Latest Draft (ECMA-262) String.prototype.search |
Draft |
浏览器兼容性
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
search |
Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 4 | Opera Full support Yes | Safari Full support Yes | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support 1.0 | nodejs Full support Yes |
flags
|
Chrome No support No | Edge No support No | Firefox No support 1 — 49 | IE No support No | Opera No support No | Safari No support No | WebView Android No support No | Chrome Android No support No | Firefox Android No support 4 — 49 | Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No | nodejs No support No |
Legend
- Full support
- Full support
- No support
- No support
- Non-standard. Expect poor cross-browser support.
- Non-standard. Expect poor cross-browser support.
- Deprecated. Not for use in new websites.
- Deprecated. Not for use in new websites.
Gecko 注意事项
- 在 Gecko 8.0 及之前的版本,
search()
的实现有问题:在调用该方法时,若不传递参数或者参数为undefined
,该方法将不会匹配空字符串,而是匹配字符串 "undefined"。这个问题已被修复,现在,"a".search()
和"a".search(undefined)
都能正确返回 0。 - Starting with Gecko 39 (Firefox 39 / Thunderbird 39 / SeaMonkey 2.36), the non-standard
flags
argument is deprecated and throws a console warning (bug 1142351). - Starting with Gecko 47 (Firefox 47 / Thunderbird 47 / SeaMonkey 2.44), the non-standard
flags
argument is no longer supported in non-release builds and will soon be removed entirely (bug 1245801). - Starting with Gecko 49 (Firefox 49 / Thunderbird 49 / SeaMonkey 2.46), the non-standard
flags
argument is no longer supported (bug 1108382).