从另一个函数调用 RowDataBound
本文关键字：RowDataBound 函数调用 另一个 | 更新日期: 2023-09-27 18:34:45
我有一个 2 个网格视图。第一个网格有一个按钮，单击该按钮时，它将使用基于所单击按钮 id 的数据填充第二个网格。
然后，我在 RowDataBound 函数中使用代码来显示基于所选行的网格。但问题是代码在填充函数之前自动运行 RowDataBound。因此，第二个网格未显示。
网格视图的代码：
<asp:GridView style="width:75%"
ID="gvCVRT"
ShowHeaderWhenEmpty="true"
CssClass="tblResults"
runat="server"
OnRowDataBound="gvCVRT_RowDataBound"
OnSelectedIndexChanged="gridviewParent_SelectedIndexChanged"
DataKeyField="ID"
DataKeyNames="ChecklistID"
AutoGenerateColumns="false"
allowpaging="false"
AlternatingRowStyle-BackColor="#EEEEEE">
<HeaderStyle CssClass="tblResultsHeader" />
<Columns>
<asp:BoundField DataField="ChecklistID" HeaderText="ID" ></asp:BoundField>
<asp:CommandField ShowSelectButton="True" HeaderText="Select" />
<asp:BoundField DataField="ChecklistDate" HeaderText="Checklist Date" dataformatstring="{0:dd/MM/yyyy}"></asp:BoundField>
<asp:BoundField DataField="User" HeaderText="User" ></asp:BoundField>
<asp:BoundField DataField="Note" HeaderText="Note" ></asp:BoundField>
</Columns>
</asp:GridView>
代码隐藏：
protected void gvCVRT_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
lookupCVRT work = (lookupCVRT)e.Row.DataItem;
GridView gv = sender as GridView;
if (work.ID != null)
{
int index = gv.Columns.HeaderIndex("Select");
if (index > -1)
{
e.Row.Cells[index].Attributes.Add("class", "gvCVRTRow");
e.Row.Cells[index].ToolTip = "Click here to Edit Checklist";
}
}
}
}
选择按钮的代码：
protected void gridviewParent_SelectedIndexChanged(object sender, EventArgs e)
{
List<lookupCVRT> workDetails = lookupCVRT.GetChecklistItemsByChecklistID(Company.Current.CompanyID, ParentID.ToString(), gvCVRT.SelectedDataKey.Value.ToString());
gvCVRTDetails.DataSource = workDetails;
gvCVRTDetails.DataBind();
FireJavascriptCallback("setArgAndPostBack ();");
}
所以问题是当我单击网格中的"选择"按钮时，它首先运行RowDataBound，然后运行gridviewParent_SelectedIndexChanged但我需要先运行gridviewParent_SelectedIndexChanged。我可以从gridviewParent_SelectedIndexChanged调用RowDataBound函数吗？
Page_Load功能：
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
GetChecklistID = "";
if (ParentID.HasValue)
{
ViewState["ParentID"] = ParentID;
List<lookupCVRT> work = lookupCVRT.GetCVRTItems(Company.Current.CompanyID, ParentID.ToString());
ViewState["CVRT"] = work;
gvCVRT.DataSource = work;
gvCVRT.DataBind();
}
}
else
{
if (ViewState["ParentID"] != null)
{
ParentID = (int?)ViewState["ParentID"];
List<lookupCVRT> work = ViewState["CVRT"] as List<lookupCVRT>;
gvCVRT.DataSource = work;
gvCVRT.DataBind();
}
}
}
仅当调用了GridView的DataBind方法时，才会调用 OnRowDataBound 事件。
在您的特定情况下，问题Page_Load在Page.IsPostBack条件的else分支中：
else
{
if (ViewState["ParentID"] != null)
{
ParentID = (int?)ViewState["ParentID"];
List<lookupCVRT> work = ViewState["CVRT"] as List<lookupCVRT>;
gvCVRT.DataSource = work;
gvCVRT.DataBind();
}
}
此代码针对每个回发运行。除非在代码中的其他位置重置ViewState["ParentID"]，否则在每次回发时，都会再次绑定 GridView gvCVRT。这就是调用RowDataBound的原因。完成Page_Load后，页面将调用其他事件处理程序，在您的情况下gridviewParent_SelectedIndexChanged 。
为了解决此问题，您需要更改Page_Load处理程序中的代码，以便没有调用回发DataBind：
// field moved to class level so that you can access this variable instead of a DataRow in gvCVRT
private List<lookupCVRT> work;
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
GetChecklistID = "";
if (ParentID.HasValue)
{
ViewState["ParentID"] = ParentID;
work = lookupCVRT.GetCVRTItems(Company.Current.CompanyID, ParentID.ToString());
ViewState["CVRT"] = work;
gvCVRT.DataSource = work;
gvCVRT.DataBind();
}
}
else
{
if (ViewState["ParentID"] != null)
{
ParentID = (int?)ViewState["ParentID"];
work = ViewState["CVRT"] as List<lookupCVRT>;
}
}
}
问题的根本原因是您需要回发请求中的数据，并且您将其放入ViewState["CVRT"]而不是重新请求数据。在Web应用程序中，再次读取新请求的数据是很常见的。因此，您可能会考虑是否确实需要将数据放入 ViewState，或者是否可以在从数据源回发时请求数据。
将数据放入 ViewState 会增加传输到客户端的页面的大小(基本上，您有 GridView 的 HTML，此外，您在 ViewState 中也有数据(。因此，在大多数情况下，重新请求它们是更好的方法。
我不知道
为什么你更喜欢使用gridviewParent_SelectedIndexChanged然后grdParent_RowDataBound......我为您创建了一个简单的解决方案..它可以帮助你..
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<div>
<label>Parent Grid</label>
<asp:GridView ID="grdParent" runat="server" AutoGenerateColumns="false"
DataKeyField="Id" OnRowDataBound="grdParent_RowDataBound" OnRowCommand="grdParent_RowCommand">
<Columns>
<asp:BoundField DataField="Name" HeaderText="Name" />
<asp:ButtonField CommandName="Details" HeaderText="Select" Text="Hello" ButtonType="Link" />
</Columns>
</asp:GridView>
</div>
<div>
<label>child Grid</label>
<asp:GridView ID="grdChild" runat="server" AutoGenerateColumns="false"
DataKeyNames="ChildId" OnRowDataBound="grdChild_RowDataBound">
<Columns>
<asp:BoundField DataField="Name" />
<asp:BoundField DataField="Roll" />
<asp:ImageField HeaderText="Image" />
</Columns>
</asp:GridView>
</div>
</div>
</form>
</body>
</html>
代码隐藏
public partial class Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
List<ParentClass> pList = new List<ParentClass>()
{
new ParentClass{Id=5, Name="V"},
new ParentClass{Id=6,Name="VI"},
new ParentClass{Id=7,Name="VII"},
new ParentClass{Id=8,Name="VIII"},
new ParentClass{Id=9,Name="IX"},
new ParentClass{Id=10,Name="X"},
};
grdParent.DataSource = pList;
grdParent.DataBind();
}
}
protected void grdParent_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.DataItem == null || e.Row.RowType != DataControlRowType.DataRow)
{
return;
}
ParentClass p = e.Row.DataItem as ParentClass;
var btn = e.Row.Cells[1].Controls[0] as LinkButton;
btn.CommandArgument = p.Id.ToString();
}
protected void grdParent_RowCommand(object sender, GridViewCommandEventArgs e)
{
int parentId = Convert.ToInt32(e.CommandArgument);
var releventStudents = GetRepositary().FindAll(i => i.ParentId == parentId);
grdChild.DataSource = releventStudents;
grdChild.DataBind();
}
protected void grdChild_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.DataItem == null || e.Row.RowType != DataControlRowType.DataRow)
{
return;
}
//lookupCVRT work = (lookupCVRT)e.Row.DataItem;
//GridView gv = sender as GridView;
//if (work.ID != null)
//{
// int index = gv.Columns.HeaderIndex("Select");
// if (index > -1)
// {
// e.Row.Cells[index].Attributes.Add("class", "gvCVRTRow");
// e.Row.Cells[index].ToolTip = "Click here to Edit Checklist";
// }
//}
}
private List<ChildClass> GetRepositary()
{
List<ChildClass> allChild = new List<ChildClass>();
Random r = new Random();
for (int i = 0; i < 50; i++)
{
ChildClass c = new ChildClass
{
ChildId = i,
ParentId = r.Next(5, 10),
Name = "Child Name " + i,
Roll = i
};
allChild.Add(c);
}
return allChild;
}
}
public class ParentClass
{
public int Id { get; set; }
public string Name { get; set; }
}
public class ChildClass
{
public int ParentId { get; set; }
public int ChildId { get; set; }
public int Roll { get; set; }
public string Name { get; set; }
}