<script language="javascript">

//参数一为被替换的字符串 参数二为被匹配的字符串 参数三为替换后的字符串

function replaceAll(str, sptr, sptr1){

while (str.indexOf(sptr) >= 0)

{

? str = str.replace(sptr, sptr1);

}

return str;

}

var a = "abcdddacfffaffff";

var b = "a";

var c = "";

var d= replaceAll(a,b,c)

alert(d);

</script>

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