javascript在文本区域的特定位置插入文本

Question

I write a form that inserts some xml tags into textarea. I use this function:

    (function ($) {
     addCustomTag = function (name, param, value) {
         var code = "<" + name + " " + param + "=\"" + value + "\">\n</" + name + ">";
         document.getElementById("codeArea").value += code;
     };
 })(jQuery);

How can I make that some other function will insert subtags into tags that were created before? XML code will never be used on server. All I need is to insert tex in specific line which is depends on what was on this line before not cutting it. Something like this:

    addCustomSubtag = function(name,param,value,parent) {
    document.getElementById("codeArea").selectionStart = document.getElementById("codeArea").value - parent.length;
    var code = "<" + name + " " + param + "=\"" + value + "\">\n</" + name + ">";
    document.getElementById("codeArea").value += code;
};

Javascript isn't necessary. It also can be written on jQuery. Thanks.

Answer 1

这可能会很有用： http : //dwieeb.github.com/jquery-textrange/

Answer 2

You can any of these jQuery functions

• http://api.jquery.com/append/
• http://api.jquery.com/appendTo/
• http://api.jquery.com/prepend/

Update:

Actually we can use jQuery DOM manipulation methods to manipulate XML also.

var xml = "<main/>";
alert(xml);                                  // <main/>
var $xml = $(xml).append($("<sub1/>"));
alert($xml.html());                          // <sub1></sub1>
$xml.find("sub1").append($("<sub2/>"));
alert($xml.html());                          // <sub1><sub2></sub2></sub1>
alert($xml.get(0).outerHTML);                // <main><sub1><sub2></sub2></sub1></main>