if(document.selection){    //IE    var selectRange = document.selection.createRange();    if(selectRange.text.length > 0){        word = selectRange.text;    }}else if(window.getSelection){    //FF 标准浏览器    word = window.getSelection().toString();}else if(document.getSelection){    //一个比较老的方法    word = document.getSelection();}

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