根据表头排序Js文件

$(document).ready(function(){
    var dom = (document.getElementsByTagName) ? true : false;
    var ie5 = (document.getElementsByTagName && document.all) ? true : false;
    var arrowUp, arrowDown;
    if (ie5 || dom)
    initSortTable();
    function initSortTable() {
        arrowUp = document.createElement("SPAN");
        var tn = document.createTextNode("5");
        arrowUp.appendChild(tn);
        arrowUp.className = "arrow";
        arrowDown = document.createElement("SPAN");
        var tn = document.createTextNode("6");
        arrowDown.appendChild(tn);
        arrowDown.className = "arrow";
    }
    function sortTable(tableNode, nCol, bDesc, sType) {
        var tBody = tableNode.tBodies[0];
        var trs = tBody.rows;
        var trl= trs.length;
        var a = new Array();
        for (var i = 0; i < trl; i++) {
        a[i] = trs[i];
    }
    var start = new Date;
    window.status = "Sorting data...";
    a.sort(compareByColumn(nCol,bDesc,sType));
    window.status = "Sorting data done";
    for (var i = 0; i < trl; i++) {
    tBody.appendChild(a[i]);
    window.status = "Updating row " + (i + 1) + " of " + trl +
    " (Time spent: " + (new Date - start) + "ms)";
    }
    // check for onsort
    if (typeof tableNode.onsort == "string")
        tableNode.onsort = new Function("", tableNode.onsort);
    if (typeof tableNode.onsort == "function")
        tableNode.onsort();
    }
    function CaseInsensitiveString(s) {
        return String(s).toUpperCase();
    }
    function parseDate(s) {
        return Date.parse(s.replace(/\/-/g, '/'));
    }
    function toNumber(s) {
        return Number(s.replace(/[^0-9/.]/g, ""));
    }
    function compareByColumn(nCol, bDescending, sType) {
        var c = nCol;
        var d = bDescending;
        var fTypeCast = String;
        if (sType == "Number")
        fTypeCast = Number;
        else if (sType == "Date")
        fTypeCast = parseDate;
        else if (sType == "CaseInsensitiveString")
        fTypeCast = CaseInsensitiveString;
        return function (n1, n2) {
        if (fTypeCast(getInnerText(n1.cells[c])) < fTypeCast(getInnerText(n2.cells[c])))
        return d ? -1 : +1;
        if (fTypeCast(getInnerText(n1.cells[c])) > fTypeCast(getInnerText(n2.cells[c])))
        return d ? +1 : -1;
        return 0;
        };
    }
    function sortColumnWithHold(e) {
        // find table element
        var el = ie5 ? e.srcElement : e.target;
        var table = getParent(el, "TABLE");
        // backup old cursor and onclick
        var oldCursor = table.style.cursor;
        var oldClick = table.onclick;
        // change cursor and onclick 
        table.style.cursor = "wait";
        table.onclick = null;
        // the event object is destroyed after this thread but we only need
        // the srcElement and/or the target
        var fakeEvent = {srcElement : e.srcElement, target : e.target};
        // call sortColumn in a new thread to allow the ui thread to be updated
        // with the cursor/onclick
        window.setTimeout(function () {
        sortColumn(fakeEvent);
        // once done resore cursor and onclick
        table.style.cursor = oldCursor;
        table.onclick = oldClick;
        }, 100);
    }
    $(".MyHeadTab").click(function(e){
        var tmp = e.target ? e.target : e.srcElement;
        var tHeadParent = getParent(tmp, "THEAD");
        var el = getParent(tmp, "TD");
        if (tHeadParent == null)
        return;
        if (el != null) {
        var p = el.parentNode;
        var i;
        // typecast to Boolean
        el._descending = !Boolean(el._descending);
        if (tHeadParent.arrow != null) {
            if (tHeadParent.arrow.parentNode != el) {
            tHeadParent.arrow.parentNode._descending = null; //reset sort order 
            }
            tHeadParent.arrow.parentNode.removeChild(tHeadParent.arrow);
        }
        if (el._descending)
            tHeadParent.arrow = arrowUp.cloneNode(true);
        else
            tHeadParent.arrow = arrowDown.cloneNode(true);
        el.appendChild(tHeadParent.arrow);
        var cells = p.cells;
        var l = cells.length;
        for (i = 0; i < l; i++) {
            if (cells[i] == el) break;
        }
        var table = getParent(el, "TABLE");
        sortTable(table,i,el._descending, el.getAttribute("type"));
        }
    })
    function getInnerText(el) {
        if (ie5) return el.innerText; //Not needed but it is faster
        var str = "";
        var cs = el.childNodes;
        var l = cs.length;
        for (var i = 0; i < l; i++) {
            switch (cs[i].nodeType) {
                case 1: //ELEMENT_NODE
                str += getInnerText(cs[i]);
                break;
                case 3: //TEXT_NODE
                str += cs[i].nodeValue;
                break;
            }
        }
        return str;
    }
    function getParent(el, pTagName) {
    if (el == null) return null;
    else if (el.nodeType == 1 && el.tagName.toLowerCase() == pTagName.toLowerCase()) // Gecko bug, supposed to be uppercase
    return el;
    else
    return getParent(el.parentNode, pTagName);
    }
})