Javascript中replace的用法

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  第一次發現JavaScript中replace() 方法如果直接用str.replace("-","!") 只會替換第一個匹配的字符.
  2而str.replace(//-/g,"!")則可以替換掉全部匹配的字符（g爲全局標誌）。
  3
  4
  5replace()
  6The replace() method returns the string that results when you replace text matching its first argument
  7(a regular expression) with the text of the second argument (a string).
  8If the g (global) flag is not set in the regular expression declaration, this method replaces only the first
  9occurrence of the pattern. For example,
  10
  11var s = "Hello. Regexps are fun.";s = s.replace(//./, "!"); // replace first period with an exclamation pointalert(s);
  12
  13produces the string “Hello! Regexps are fun.” Including the g flag will cause the interpreter to
  14perform a global replace, finding and replacing every matching substring. For example,
  15
  16var s = "Hello. Regexps are fun.";s = s.replace(//./g, "!"); // replace all periods with exclamation pointsalert(s);
  17
  18yields this result: “Hello! Regexps are fun!”