我尝试了下面的排序功能
<asp:GridView ID="grdUser"
AllowPaging="true"
AutoGenerateColumns="False"
OnDataBound="grdUser_DataBound"
OnRowDeleting="grdUser_RowDeleting"
OnPreRender="PreRenderGrid"
runat="server"
Width="100%"
border="1"
DataKeyNames="Id"
PageSize="10"
EmptyDataText="No Records Found"
OnPageIndexChanging="grdUser_PageIndexChanging"
EnableSortingAndPagingCallbacks="false"
CssClass="hoverTable"
AllowSorting="true"
OnSorting="grdUser_Sorting"
ShowFooter="false"
HeaderStyle-CssClass="k-grid td"
OnRowCommand="grdUser_RowCommand">
<AlternatingRowStyle CssClass="k-alt" />
<Columns>
<asp:TemplateField HeaderText="Select" ItemStyle-Width="5">
<ItemTemplate>
<asp:CheckBox ID="chkDelete" runat="server" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="username" HeaderText="Username" SortExpression="username" ItemStyle-Width="30" />
<asp:BoundField DataField="email" HeaderText="Email ID" SortExpression="email" ItemStyle-Width="30" />
<asp:BoundField DataField="ngoname" HeaderText="NGO Name" ItemStyle-Width="30" />
<asp:BoundField DataField="usertype" HeaderText="UserType" ItemStyle-Width="30" Visible="false" />
<asp:BoundField DataField="UserRoleName" HeaderText="User Role" ItemStyle-Width="30" />
<asp:BoundField DataField="active" HeaderText="Active" SortExpression="active" ItemStyle-Width="30" />
<asp:TemplateField HeaderText="Action" HeaderStyle-Width="5%">
<ItemTemplate>
<asp:ImageButton ID="btnEdit" AlternateText="Edit" ImageUrl="~/images/edit.png" ToolTip="Edit" runat="server" Width="15" Height="15" CommandName="eEdit" CommandArgument='<%# Eval("Id") %>' CausesValidation="false" />
<asp:ImageButton ID="btnDelete" AlternateText="Delete" ImageUrl="~/images/delete.png" ToolTip="Delete" runat="server" Width="15" Height="15" CommandName="Delete" CommandArgument='<%# Eval("Id") %>' CausesValidation="false" OnClientClick="return confirm('Are you sure you want to delete this record?')" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
另见我背后的代码： -
protected void grdUser_Sorting(object sender, GridViewSortEventArgs e)
{
DataTable dt = Session["tbl_User"] as DataTable;
DataView dataView = new DataView(dt);
dataView.Sort = e.SortExpression + " " + GetSortDirection(e.SortExpression);
grdUser.DataSource = dataView;
grdUser.DataBind();
}
private string GetSortDirection(string column)
{
string sortDirection = "ASC";
string sortExpression = ViewState["SortExpression"] as string;
if (sortExpression != null)
{
if (sortExpression == column)
{
string lastDirection = ViewState["SortDirection"] as string;
if ((lastDirection != null) && (lastDirection == "ASC"))
{
sortDirection = "DESC";
}
}
}
ViewState["SortDirection"] = sortDirection;
ViewState["SortExpression"] = column;
return sortDirection;
}
但是当我调试代码时，我总是将dt视为null。 请帮忙
更新
绑定gridview的代码： -
protected void BindGrid()
{
string username = string.Empty;
string usertype = string.Empty;
try
{
SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["DefaultCSRConnection"].ConnectionString);
SqlCommand cmd = new SqlCommand("SELECT usertype,username FROM tbl_User WHERE username=@username", conn);
cmd.Parameters.Add("@username", SqlDbType.VarChar).Value = Session["User"].ToString();
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
if (dr.Read())
{
username = dr["username"].ToString();
usertype = dr["usertype"].ToString();
}
}
conn.Close();
string query = string.Empty;
if (!string.IsNullOrEmpty(usertype))
{
if (usertype == "0") // superadmin
{
query = "select tbl_User.Id,tbl_ngoname.ngo_name, tbl_User.username,tbl_User.email,tbl_User.usertype,tbl_User.active,(CASE WHEN tbl_User.usertype='1' THEN 'Admin' WHEN tbl_User.usertype='0' THEN 'Super Admin' WHEN tbl_User.usertype='2' THEN 'User' END) AS UserRoleName FROM tbl_User INNER JOIN tbl_ngoname on tbl_ngoname.Id = tbl_User.NgoId ORDER By Id DESC";
}
if (usertype == "1") // admin
{
query = "select tbl_User.Id,tbl_ngoname.ngo_name, tbl_User.username,tbl_User.email,tbl_User.usertype,tbl_User.active,(CASE WHEN usertype='1' THEN 'Admin' WHEN usertype='0' THEN 'Super Admin' WHEN usertype='2' THEN 'User' END) AS UserRoleName from tbl_User INNER JOIN tbl_ngoname on tbl_ngoname.Id = tbl_User.NgoId WHERE usertype != '0' ORDER By Id DESC";
}
if (usertype == "2") // user
{
query = "select tbl_User.Id,tbl_ngoname.ngo_name, tbl_User.username,tbl_User.email,tbl_User.usertype,tbl_User.active,(CASE WHEN usertype='1' THEN 'Admin' WHEN usertype='0' THEN 'Super Admin' WHEN usertype='2' THEN 'User' END) AS UserRoleName from tbl_User INNER JOIN tbl_ngoname on tbl_ngoname.Id = tbl_User.NgoId WHERE username='" + username + "' ORDER By Id DESC";
}
cmd = new SqlCommand(query, conn);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
grdUser.DataSource = ds.Tables[0];
grdUser.DataBind();
DisablePageDirections();
grdUser.BottomPagerRow.Visible = true;
Session["tbl_User"] = ds.Tables[0];
}
}
catch (Exception)
{
throw;
}
}
添加更多代码： -
private DataTable GetData(SqlCommand cmd)
{
DataTable dt = new DataTable();
SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["DefaultCSRConnection"].ConnectionString);
SqlDataAdapter sda = new SqlDataAdapter();
cmd.Connection = conn;
try
{
conn.Open();
sda.SelectCommand = cmd;
sda.Fill(dt);
return dt;
}
catch (Exception ex)
{
throw ex;
}
finally
{
conn.Close();
sda.Dispose();
conn.Dispose();
}
}
答案 0 :(得分：1)
您在页面加载时设置名为tbl_user的会话，当您获得该会话时，您将使用GridViewData。
在页面加载时，您使用名称tbl_user
设置会话Session["tbl_User"] = dt;
你得到的名字是GridViewData
DataTable dt = Session["GridViewData"] as DataTable;
当您从grdUser_Sorting中的会话中获取数据表时，请将其更改为
protected void grdUser_Sorting(object sender, GridViewSortEventArgs e)
{
//Retrieve the table from the session object.
DataTable dt = Session["tbl_user"] as DataTable;
if (dt != null)
{
//Sort the data.
dt.DefaultView.Sort = e.SortExpression + " " + GetSortDirection(e.SortExpression);
grdUser.DataSource = Session["tbl_user"];
grdUser.DataBind();
}
}