各位大侠，谁那里有用js添加div，并且可以移动div的代码呀，谢谢

我用这个怎么不能行呀，
var divId = 1;
function f_adddiv() {
    var obj = document.createElement("div");
    obj.id = "myDiv" + divId;
    divId++;
    obj.style.border = "0px solid #000000";
    obj.style.height = "30px";
    obj.style.width = "60px";
    obj.style.filter = "alpha(opacity=70)";
    obj.style.margin = "10px";
    obj.style.cursor = "hand";
    obj.algin = "center";
    obj.style.position = "relative";
    //obj.innerHTML="<a href='#"+obj.id+"'>ssssssssss</a>";
    obj.innerHTML="<img src='../bmp/shichanglf.gif' alt=''><br/><input id='txt_name"+divId +"'  type='text' style='width:60px'  value='你好'>";
   // obj.innerText = "<img src='../bmp/loufang.gif' alt=''>";
    document.body.appendChild(obj);
    document.getElementById(obj.id).onmousedown = function() { movetianyamessage(obj, event); };
    document.getElementById(obj.id).onmousemove = function() { movetianyamessageend(event); };
    document.getElementById(obj.id).onmouseup = function() { movetianyamessageend(event); };
    document.getElementById(obj.id).onmouseout = function() { movetianyamessageend(event); };
   
}// javascript文件 
/*调用方法 
//onmousedown="movetianyamessage(div_Info, event)" onmousemove="movetianyamessageend(event);" 
//onmouseup="movetianyamessageend(event)" onmouseout="movetianyamessageend(event)" 
//onmousedown=鼠标点下的时候 onmousemove=鼠标经过的时候 onmouseup=鼠标弹起来的时候 onmouseout=鼠标离开的时候 
*/
var tianyamessage = ''
var iLayerMaxNum = 999;
document.onmouseup = movetianyamessageend;
document.onmousemove = movetianyamessagestart;
var tianyamessagepixefX;
var tianyamessagepixefY;
function movetianyamessage(Object, event) {
    tianyamessage = Object.id;
    if (document.all) {
        document.getElementById(tianyamessage).setCapture();
        tianyamessagepixefX = event.x - document.getElementById(tianyamessage).style.pixelLeft;
        tianyamessagepixefY = event.y - document.getElementById(tianyamessage).style.pixelTop;
    }
    else if (window.captureEvents) {
        window.captureEvents(Event.MOUSEMOVE | Event.MOUSEUP);
        tianyamessagepixefX = event.layerX;
        tianyamessagepixefY = event.layerY;
    }
    document.getElementById(tianyamessage).style.zIndex = iLayerMaxNum;
    iLayerMaxNum = iLayerMaxNum + 1;
}
function movetianyamessagestart(evt) {
    if (tianyamessage != '') {
        if (document.all) {
            document.getElementById(tianyamessage).style.left = event.x - tianyamessagepixefX;
            document.getElementById(tianyamessage).style.top = event.y - tianyamessagepixefY;
        }
        else if (window.captureEvents) {
            document.getElementById(tianyamessage).style.left = (evt.clientX - tianyamessagepixefX) + "px";
            document.getElementById(tianyamessage).style.top = (evt.clientY - tianyamessagepixefY) + "px";
        }
    }
}
function movetianyamessageend(evt) {
    if (tianyamessage != '') {
        if (document.all) {
            document.getElementById(tianyamessage).releaseCapture();
            tianyamessage = '';
        }
        else if (window.captureEvents) {
            window.captureEvents(Event.MOUSEMOVE | Event.MOUSEUP);
            tianyamessage = '';
        }
    }
}
function disponse_div(obj) {
    if (obj.style.display == "block") {
        obj.style.display = "none";
    }
    else {
        obj.style.display = "block";
    }
}