RegExp.prototype.source - JavaScript 编辑

The source property returns a String containing the source text of the regexp object, and it doesn't contain the two forward slashes on both sides and any flags.

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.

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.

Property attributes of RegExp.prototype.source
Writable	no
Enumerable	no
Configurable	yes

Examples

Using source

var regex = /fooBar/ig;

console.log(regex.source); // "fooBar", doesn't contain /.../ and "ig".

Empty regular expressions and escaping

Starting with ECMAScript 5, the source property no longer returns an empty string for empty regular expressions. Instead, the string (?:) is returned. In addition, line terminators (such as "\n") are escaped now.

new RegExp().source; // "(?:)"

new RegExp('\n').source === '\n';  // true, prior to ES5
new RegExp('\n').source === '\\n'; // true, starting with ES5

Specifications

Specification
ECMAScript (ECMA-262) The definition of 'RegExp.prototype.source' in that specification.

Browser compatibility

BCD tables only load in the browser

See also

• RegExp.prototype.flags