<script type="text/javascript"> var str = "12345&type=png"; var m =str.length; var n = str.indexOf('='); var j = str.substring(n+1,m); var s = str.replace(j,'jpg'); alert(j) alert(s);
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第2个回答 推荐于2016-11-16
<script type="text/javascript"> var str = "12345&type=png"; var m =str.length; var n = str.indexOf('='); var j = str.substring(n+1,m); var s = str.replace(j,'jpg'); alert(j) alert(s);