第一次发现JavaScript中replace() 方法如果直接用str.replace("-","!") 只会替换第一个匹配的字符. 而str.replace(/\-/g,"!")则可以全部替换掉匹配的字符(g为全局标志)。 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!” [b]所以可以用以下几种方式.： [/b]string.replace(/reallyDo/g, replaceWith); string.replace(new RegExp(reallyDo, 'g'), replaceWith); [b]string：[/b]字符串表达式包含要替代的子字符串。 [b]reallyDo：[/b]被搜索的子字符串。 [b]replaceWith：[/b]用于替换的子字符串。