JS无限添加HTML到指定位置

用JS把HTML添加到指定位置有两种写法，一种是用字符串，一种是用javascript中的方法

第一种：

用字符串写

<h2>利用JS无限添加一个相同部分</h2>
        <h5>第一种写法</h5>
        <%--有多少个相同的这里面的值就是几--%>
        <asp:HiddenField ID="hfCount" runat="server" Value="-1" />
        <%--每个就是后面的数字不一样 例如：One1,One2,One3....      --%>
        <asp:HiddenField ID="hfIndex" runat="server" />
        <div id="divOne" runat="server">
       <%-- 这里添加HTML --%>
        </div>
        <span class="addto"><a href="javascript:void(0);" onclick="AddInfo();">添加</a></span>
        <br />
        <hr />

  <script type="text/javascript">
            $(function () {
                var count = $("#hfCount").val();
                if (count <= 0) {
                    AddInfo();
                }
            })

            function AddInfo() {
              ①
                //根据数量来增加   hfCount的值   
                var Count = $("#hfCount").val();  //先取值
                var PageIndex = 0;
                //如果没有就自己加，有就根据个数来定
                if (Count > -1) {
                    var Indexs = $("#hfIndex").val().split(',');  //有多少个dl
                    Count = ++Indexs[Count - 1];  //第几个  取最大值 +1就可以
                    PageIndex = Indexs.length - 1;  //个数

                } else {
                    Count++;
                    PageIndex = Count;
                }
                  
             //第二种赋值，用这种下面的也要变   

            ②   字符串生成dl里面的Count改成PageIndex

             var OneCount = $("#OneCount").val(); //取个数

               var pageIndex = 0;
               if (OneCount > 0) {
                   var OneIndexs = $("#OneIndex").val(); //0,1,2,3,4
                   var Indexs = OneIndexs.split(','); //0 1 2 3 4 ""
                   pageIndex = ++Indexs[Indexs.length - 2]; //取最大值每次+1就是下一个数字
               }

                var strHtml = "
";
                strHtml += "<dl class='form_main' id="Form" + Count + "">
";
                //这里绑定表的主键  好做修改
                strHtml += "<input type="hidden" name="hfID" + Count + "" value="0"/>
";

                strHtml += "<dd>
";
                strHtml += "<u>测试数据一：</u>
";
                strHtml += "<input type='text' id='One" + Count + "' name='One" + Count + "' />
";
                strHtml += "</dd>
";

                strHtml += "<dd>
";
                strHtml += "<u>测试数据二：</u>
";
                strHtml += "<input type='text' id="Two" + Count + "" name='" + Count + "' />
";
                strHtml += "</dd>
";

                if (Count > 0) {
                    strHtml += "<dt class="delete"><a href="javascript:void(0);" onclick="delControl('Form" + Count + "')" >删除</a></dt>
";
                }
                strHtml += "<dt></dt>
";
                strHtml += "</dl>";
                  //字符串拼接好
             ①

                $("#divOne").append(strHtml);
                $("#hfCount").val(++PageIndex);
                var dd = $("#hfIndex").val();
                dd += Count + ",";
                $("#hfIndex").val(dd);

             ②

               $("#OneCount").val(parseInt(OneCount) + 1);   //数量加一
               var OneIndex = $("#OneIndex").val();            //先取值
               $("#OneIndex").val(OneIndex + pageIndex + ",");    //在原来的值上添加新的值

            }

             //删除
             ①

            function delControl(id) {
                $("dl").remove("#" + id);
                //我们让下面的ID删除，数量减一就可以了
                var count = $("#hfCount").val(); //取值
                $("#hfCount").val(--count);    //计算后赋值
                var index = $("#hfIndex").val();  //0,1,2,3              
                index = index.replace(id.replace("Form", "") + ",", ""); //删除第几个就把 x， 删除
                $("#hfIndex").val(index);
            }
         ②

              function delControl(id) {
                $("dl").remove("#" + id);
               //重新赋值
               var OneCount = $("#OneCount").val();
　　　　　　　　 $("#OneCount").val(--OneCount); //个数重新赋值
　　　　　　　　 var dd = id.replace("Form", ""); //得到数字
　　　　　　　　 var Index = $("#OneIndex").val(); //取值
　　　　　　　　 Index = Index.replace(dd + ",", ""); //替换（也就是删除数字）
　　　　　　　　 $("#OneIndex").val(Index);
　　　　　　　　}

   

4代表是有多少个，下面的0,1,4,5,代表dl里面的数字   这个是对应的，后台取值需要

 我们来看看怎么存数据

 public List<Two> listTwo;  //一般这里存到数据库里面，然后从数据库里面取数据，做演示就简单的存一下
  public void AddOne()
    {
        listTwo = new List<Two>();
        string[] indexs = hfIndex.Value.TrimEnd(',').Split(',');   //1，5，6，7   类似的格式
        foreach (string item in indexs)
        {
            Two two = new Two();
            two.A = Request.Form["One" + item]; //表单提交，post取数据
            two.B = Request.Form["Two" + item];
            listTwo.Add(two);
        }
    }

  public class Two
    {
        public string B { get; set; }
        public string A { get; set; }

    }
//字符串的形式来赋值
   public void AddHtml()
    {
        string strHtml = "
";
        divOne.InnerHtml = "";
        if (listTwo != null)
        {
            hfCount.Value = listTwo.Count + "";
            for (int i = 0; i < listTwo.Count; i++)
            {
                strHtml += "<dl class='form_main' id="Form" + i + "">
";
                //这里绑定表的主键  好做修改
                strHtml += "<input type="hidden" name="hfID" + i + "" value="0"/>
";

                strHtml += "<dd>
";
                strHtml += "<u>测试数据一：</u>
";
                strHtml += "<input type='text' id='One" + i + "' name='One" + i + "' value="" + listTwo[i].A + "" />
";
                strHtml += "</dd>
";

                strHtml += "<dd>
";
                strHtml += "<u>测试数据二：</u>
";
                strHtml += "<input type='text' id="Two" + i + "" name='Two" + i + "' value="" + listTwo[i].B + "" />
";
                strHtml += "</dd>
";

                if (i > 0)
                {
                    strHtml += "<dt class="delete"><a href="javascript:void(0);" onclick="delControl('Form" + i + "')" >删除</a></dt>
";
                }
                strHtml += "<dt></dt>
";
                strHtml += "</dl> ";

                hfIndex.Value = hfIndex.Value + i + ",";
            }
            divOne.InnerHtml = strHtml;

        }
    }

第二种，利用Javascript创建元素来写

   <h5>第二种写法</h5>
        <div id="divHtml" runat="server">
        </div>
        <asp:HiddenField ID="hfTest" Value="0" runat="server" />
        <span class="addto"><a href="javascript:void(0);" onclick="AddHtml();">添加</a></span>

      function AddHtml() {
                var count = $("#hfTest").val();
                var divHtml = document.getElementById("divHtml");
                var newdl = document.createElement("dl"); //创建一个元素
                newdl.setAttribute("class", "form_main");   //设置属性
                newdl.setAttribute("id", "FormOne" + count);

                //创建第一个dd
                var newdd0 = document.createElement("dd"); //创建一个子元素
            
                //u
                var newu0 = document.createElement("u");
                newu0.innerHTML = "测试数据One";  //设置文本
                newdd0.appendChild(newu0);   //dd里面添加 u
                //input
                var newinput0 = document.createElement("input");
                newinput0.setAttribute("id", "DataOne" + count);
                newinput0.setAttribute("Name", "DataOne" + count);
                newinput0.setAttribute("type", "text");

                newdd0.appendChild(newinput0);   //dd里面添加 input
                newdl.appendChild(newdd0);          //dl里面添加dd

                //第二个
                var newdd1 = document.createElement("dd");
             
                ////u
                var newu1 = document.createElement("u");
                newu1.innerText = "测试数据Two";  
                newdd1.appendChild(newu1);
                //input
                var newinput1 = document.createElement("input");
                newinput1.setAttribute("type", "text");
                newinput1.setAttribute("id", "DataTwo" + count);
                newinput1.setAttribute("Name", "DataTwo" + count);

                newdd1.appendChild(newinput1);
                newdl.appendChild(newdd1);
                if (count > 0) {
                    //创建删除
                    var newdeldt = document.createElement("dt");
                    newdeldt.setAttribute("class", "delete");
                    var newa = document.createElement("a");
                    newa.setAttribute("href", "javascript:void(0)");
                    newa.setAttribute("onclick", "deleteHtml('FormOne" + count + "')");
                    newa.innerHTML = "删除";
                    newdeldt.appendChild(newa);
                    newdl.appendChild(newdeldt);
                }
                var dt = document.createElement("dt");
                newdl.appendChild(dt);
                divHtml.appendChild(newdl);  //把dl添加到div里面
                count++;
                $("#hfTest").val(count);
            }

            function deleteHtml(id) {
                $("#" + id).remove();
                var count = $("#hfTest").val();
                count--;
                $("#hfTest").val(count--);
               //个数   并保证 dl的id以xx0,xx1,xx2，xx3的规律
                var i = 0;
                $("#divHtml dl").each(function () {
                    //设置每个dl的属性，方便后台取值
                    $(this).attr("id","FormOne" + i);
                    $(this).children("dd:eq(0)").find("input").attr({ "id": "DataOne" + i, "name": "DataOne"+i });
                    $(this).children("dd:eq(1)").find("input").attr({ "id": "DataTwo" + i, "name": "DataTwo" + i });
                    $(this).children("dt[class='delete']").attr("onclick", "deleteHtml('FormOne" + i + "')");
                    i++;
                })
            }

页面

 生成的HTML，id很有规律

 

后台存和取值

using System.Web.UI.HtmlControls;   //先引用
public List<One> listOne;
  public void CreateHtml()
    {
        divHH.InnerHtml = "";
        if (listOne != null)
        {
            int i = 0;
            foreach (One item in listOne)
            {
                 //创建一个Html元素
                HtmlGenericControl newdl = new HtmlGenericControl("dl");
                newdl.Attributes.Add("class", "form_main");
                newdl.Attributes.Add("id", "FormOne" + i);
                //创建第一个dd
                HtmlGenericControl newdd1 = new HtmlGenericControl("dd");

                //创建u
                HtmlGenericControl newu1 = new HtmlGenericControl("u");
                newu1.InnerHtml = "测试数据One：";
                newdd1.Controls.Add(newu1); //把u添加到dd中

                //创建Input
                HtmlGenericControl newinput1 = new HtmlGenericControl("input");
                newinput1.Attributes.Add("id", "DataOne" + i);
                newinput1.Attributes.Add("name", "DataOne" + i);
                newinput1.Attributes.Add("type", "text");
                newinput1.Attributes.Add("value", item.Name);

                newdd1.Controls.Add(newinput1);
                newdl.Controls.Add(newdd1);

                //创建第二个dd
                HtmlGenericControl newdd2 = new HtmlGenericControl("dd");

                //u
                HtmlGenericControl newu2 = new HtmlGenericControl("u");
                newu2.InnerHtml = "测试数据Two：";
                newdd2.Controls.Add(newu2);

                //input
                HtmlGenericControl newinput2 = new HtmlGenericControl("input");
                newinput2.Attributes.Add("id", "DataTwo" + i);
                newinput2.Attributes.Add("name", "DataTwo" + i);
                newinput2.Attributes.Add("type", "text");
                newinput2.Attributes.Add("value", item.Des);

                newdd2.Controls.Add(newinput2);
                newdl.Controls.Add(newdd2);

                if (i > 0)
                {
                    //创建dt删除
                    HtmlGenericControl newdt = new HtmlGenericControl("dt");
                    newdt.Attributes.Add("class", "delete");

                    HtmlGenericControl newa = new HtmlGenericControl("a");
                    newa.Attributes.Add("href", "javascript:void(0);");
                    newa.Attributes.Add("onclick", "deleteHtml('FormOne" + i + "')");
                    newa.InnerHtml = "删除";
                    newdt.Controls.Add(newa);
                    newdl.Controls.Add(newdt);
                }
                HtmlGenericControl newdt0 = new HtmlGenericControl("dt");
                newdl.Controls.Add(newdt0);

                divHH.Controls.Add(newdl);
                i++;
                hfTest.Value = i.ToString();
            }
        }
    }

  public void Add()
    {
        int Count = Convert.ToInt32(hfTest.Value);
        listOne = new List<One>();
        for (int i = 0; i < Count; i++)
        {
            One one = new One();
            one.Name = Request.Form["DataOne" + i];
            one.Des = Request.Form["DataTwo" + i];
            listOne.Add(one);
        }
    }
    public class One
    {
        public string Des { get; set; }
        public string Name { get; set; }

    }

 以上就是两个在页面上添加HTML标签，这里只写了简单的标签，而做项目时一般都会有复杂一点的，复杂的没写进demo里面，可以自己去扩充。