GridView 无刷新分页的实现(ICallBackEventHandler-转 ）

 

http://zfnh2002.bokee.com/viewdiary.12243206.html

要想实现无刷新分页,就需要拦截GridView的PageIndexChange()事件,然后用ICallBackEventHandler实现无刷新回调.可是我发现如果GridView采用正常的分布方法的话,很难在客户端捕获到这个事件.于是我想了个办法,那就是采用模版的方式来编辑用于分页操作的Row,在模版放上我们自己添加上去的控件来实现翻页操作.具体的做法是:

1.往页面上放一个GridView,将其放置于一个DIV中.正常设置分页操作.

2.进入模版编辑界面,选择编辑Pager Template,放上用于执行分页操作的控件.我的做法是放两个LinkButton控件.ID分别设为lnkbtnPrev,lnkbtnNext.

3.在GridView1_DataBound事件中给这两个控件添加相应的客户端事件.代码如下:

        GridViewRow pagerRow = GridView1.BottomPagerRow;
        LinkButton lnkPrev = (LinkButton)pagerRow.Cells[0].FindControl("lnkbtnPrev");
        LinkButton lnkNext = (LinkButton)pagerRow.Cells[0].FindControl("lnkbtnNext");
        int newPageIndex = GridView1.PageIndex;
        lnkPrev.Enabled = false;
        lnkNext.Enabled = false;
        lnkPrev.Attributes.Remove("onclick");
        lnkNext.Attributes.Remove("onclick");
        if (newPageIndex > 0)
        {
            lnkPrev.Enabled = true;
            lnkPrev.Attributes.Add("onclick", "setPageTo(" + (newPageIndex - 1).ToString() + ");return false;");
        }
        if (newPageIndex < GridView1.PageCount - 1)
        {
            lnkNext.Enabled = true;
            lnkNext.Attributes.Add("onclick", "setPageTo(" + (newPageIndex + 1).ToString() + ");return false;");
        }

4.在客户端脚本中添加setPageTo()方法,以实现回调.

      function setPageTo(pageIndex)
      {
         var context=document.getElementById("listDIV");
         context.innerHTML="<IMG SRC='Images/pie.gif' />数据加载中...";
         var arg='pageChange|'+pageIndex;
         <%= ClientScript.GetCallbackEventReference(this, "arg", "onCallServerComplete", "context")%>;
      }

      function onCallServerComplete(result,context)
      {
         context.innerHTML=result;
      }

5.在服务器端添加用于实现回调的方法,重新生成GridView分页后的HTML代码,传回客户端.

    public void RaiseCallbackEvent(string eventArgument)
    {
        serverReturn = eventArgument;
    }
    public string GetCallbackResult()
    {
         return pageChange(int.Parse(serverReturn ));
    }

    private string pageChange(string newIndex)
    {
        int newPageIndex = int.Parse(newIndex);
             //设置数据源
        GridView1.DataBind();

        return getRenderCode();

    }

    private string getRenderCode()
    {
        StringWriter writer1 = new StringWriter(CultureInfo.InvariantCulture);
        HtmlTextWriter writer2 = new HtmlTextWriter(writer1);

        GridView1.Visible = true;
        GridView1.RenderControl(writer2);
        writer2.Flush();
        writer2.Close();

        return writer1.ToString();

    }