详解移动端html5页面长按实现高亮全选文本内容的兼容解决方案

cparea{  
    text-align: center;  
    font-family: Microsoft Yahei;  
    margin: -2em 0 0;  
}  
kwd{  
    display: inline-block;  
    color: #272727;  
    background-color: #fff;  
    font-size: 1875em;  
    font-size: 1875em;  
    padding: 75em 1em;  
    border: 1px dashed #e60012;  
    -webkit-user-select:element;   
    margin: 2em;  
}  
kwd span{  
    display: block;   
    border: 1px solid #fff;  
}  
kdes{  
    display: inline-block;  
    color: #212121;  
    font-size: 875em;  
    padding-top: 0;  
}  
kdes b{  
    color: #ed5353;  
    font-size: 25em;  
    padding-right: 1em;  
}  

$("#kwd").bind("taphold", function(){  
    var doc = document,   
        text = docgetElementById("kwd"),  
        range,   
        selection;  
    if (docbodycreateTextRange) { //IE  
        range = documentbodycreateTextRange();  
        rangemoveToElementText(text);  
        rangeselect();  
  
    } else if (windowgetSelection) {   //FF CH SF  
        selection = windowgetSelection();          
        range = documentcreateRange();  
        rangeselectNodeContents(text);  
        selectionremoveAllRanges();  
        selectionaddRange(range);  
  
        //测试  
        consolelog(texttextContent);  
        textinnerText && consolelog(textinnerText);  //FireFox不支持innerText  
        consolelog(texttextContentlength);  
        textinnerText && consolelog(textinnerTextlength);   //在Chrome下长度比IE/FF下多1  
        consolelog(textfirstChildtextContentlength);  
        textinnerText && consolelog(textfirstChildinnerTextlength);  
        consolelog(textfirstChildinnerHTMLlength);  
  
        //注意IE9-不支持textContent  
        makeSelection(0, textfirstChildtextContentlength, 0, textfirstChild);  
        /* 
        if(selectionsetBaseAndExtent){ 
            selectionselectAllChildren(text); 
            selectionsetBaseAndExtent(text, 0, text, 4); 
        } 
        */  
    }else{  
        alert("浏览器不支持长按复制功能");  
    }  
  
});  
function makeSelection(start, end, child, parent) {  
    var range = documentcreateRange();  
    //consolelog(parentchildNodes[child]);  
    rangesetStart(parentchildNodes[child], start);  
    rangesetEnd(parentchildNodes[child], end);  
  
    var sel = windowgetSelection();  
    selremoveAllRanges();  
    seladdRange(range);   
}