查询字符串中某个字符出现的位置数组

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    <title>Document</title>
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<script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"></script>
<script type="text/javascript">
$(function(){
    var str = "bdsajsbvfcsddansfkjanhfhbfshdabajh";
    var arr = [];
    var pos = str.indexOf("a");
    while(pos>-1){
        arr.push(pos);
        pos = str.indexOf("a",pos+1);
    };
    console.log(str);
    console.log(arr);
});
</script>
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