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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.
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而str.replace(/\-/g,"!")则可以替换掉全部匹配的字符(g为全局标志)。
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replace()
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The replace() method returns the string that results when you replace text matching its first argument
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(a regular expression) with the text of the second argument (a string).
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If the g (global) flag is not set in the regular expression declaration, this method replaces only the first
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occurrence of the pattern. For example,
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var s = "Hello. Regexps are fun.";s = s.replace(/\./, "!"); // replace first period with an exclamation pointalert(s);
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produces the string “Hello! Regexps are fun.” Including the g flag will cause the interpreter to
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perform a global replace, finding and replacing every matching substring. For example,
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var s = "Hello. Regexps are fun.";s = s.replace(/\./g, "!"); // replace all periods with exclamation pointsalert(s);
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yields this result: “Hello! Regexps are fun!”
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