<div>
<span>1</span>
<span>2</span>
<span>3</span>
<span>4</span>
</div>

<div id="div1">
<span>1</span>
<span>2</span>
<span>3</span>
<span>4</span>
</div>

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    var spanarr = new Array;
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    alert(spanarr.join(","));
</script>