而str.replace(//-/g,"!")則可以全部替換掉匹配的字符(g為全局標志)。 replace() The replace() method returns the string that results when you replace text matching its first argument (a regular expression) with the text of the second argument (a string). If the g (global) flag is not set in the regular expression declaration, this method replaces only the first occurrence of the pattern. For example, var s = "Hello. Regexps are fun." ;s = s.replace(//./, "!" ); // replace first period with an exclamation pointalert(s); produces the string “Hello! Regexps are fun.” Including the g flag will cause the interpreter to perform a global replace, finding and replacing every matching substring. For example, var s = "Hello. Regexps are fun." ;s = s.replace(//./g, "!" ); // replace all periods with exclamation pointsalert(s); yields this result: “Hello! Regexps are fun!” 所以可以用以下幾種方式.： string.replace(/reallyDo/g, replaceWith); string.replace(new RegExp(reallyDo, 'g'), replaceWith); string：字符串表達式包含要替代的子字符串。 reallyDo：被搜索的子字符串。 replaceWith：用于替換的子字符串。
