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);