在页面加载时丢失的数据网格中的排序

Question

//Sort User Table
private void SortGridView(string sortExpression, string direction)
{
    DataTable dataTable = BindGridView(Session["useremail"].ToString()).Tables[0];
    if (dataTable != null)
    {
        DataView dataView = new DataView(dataTable);
        dataView.Sort = sortExpression + direction;

        UserTable.DataSource = dataView;
        UserTable.DataBind();
    }
}

protected void gridView_Sorting(object sender, GridViewSortEventArgs e)
{
    string sortExpression = e.SortExpression;
    if (GridViewSortDirection == SortDirection.Ascending)
    {
        GridViewSortDirection = SortDirection.Descending;
        SortGridView(sortExpression, " ASC");
    }

    else
    {
        GridViewSortDirection = SortDirection.Ascending;
        SortGridView(sortExpression, " DESC");
    }
}

public SortDirection GridViewSortDirection
{
    get
    {
        if (ViewState["sortDirection"] == null)
            ViewState["sortDirection"] = SortDirection.Ascending;
        return (SortDirection)ViewState["sortDirection"];
    }
    set { ViewState["sortDirection"] = value; }
}

当我编辑用户并更新编辑或执行某些搜索，并清除页面加载和排序丢失的搜索时，

private DataSet BindGridView(string email)
    {
        .......
    }

 protected void btnUpdate_Click(object sender, EventArgs e)
   {
      .....
       BindGridView(Session["useremail"].ToString());
    }

每次页面加载或某些回发完成时，排序都会丢失，如何保留排序。

页面加载

 if (PermissionList.Any(item => item.Equals("Edit user")))        
     {            
            if (!IsPostBack)
            {
                BindGridView(Session["useremail"].ToString());
            }
        }

Answer 1

无论何时在网格视图上执行新的排序，将排序表达式存储在隐藏的标签或字段中，以及在任何时候重新加载/绑定网格视图，都可以使用保存的排序表达式对表进行重新排序。

.aspx

<asp:Label id="lblHidSortExp" runat="server" visible="false"></asp:Label>

.aspx.cs

protected void gridView_Sorting(object sender, GridViewSortEventArgs e)
{
    string sortExpression = lblHidSortExp.Text;
    if(sortExpression == e.SortExpression)
        sortExpression += " DESC";
    else
        sortExpression == e.SortExpression;

   //not sure if this is exactly how you get your datatable, but you get the idea
   DataView myView = new DataView(BindGridView(Session["useremail"].ToString()).Tables[0]);
   myView.Sort = sortExpression;
   marksGridView.DataSource = myView;
   marksGridView.DataBind();

   //save sort state
   lblHidSortExp.Text = sortExpression;
}

因此，假设在update函数中，使用保存排序表达式

protected void btnUpdate_Click(object sender, EventArgs e)
{
  .....//do update in db
   //reload your table in dataview
   DataView myView = new DataView(/*load table*/);
   //do sort
   myView.Sort = lblHidSortExp.Text;
   //bind gridview
   marksGridView.DataSource = myView;
   marksGridView.DataBind();
}

Answer 2

我有一个类似的问题，我解决这个问题的方法是保存会话中的排序值，然后在它们丢失后在Page_load中重置它们。