Gridview row.Cells[i].Findcontrol 在错误的单元格中查找控件
Gridview row.Cells[i].Findcontrol finding control in wrong Cell
我有一个我编写的函数，您传入 gridview 行，以及您试图定位的控件类型。它按预期找到了控件，但是，它在错误的单元格中找到了它。
protected int GetCell(GridViewRow row, string strSection)
{
int intVal = 0;
for (int i = 0; i < row.Cells.Count; i++)
{
intVal = i;
if (strSection == "QueryRate")
{
DropDownList cmbQueryType = row.Cells[i].FindControl("cmbQueryType") as DropDownList;
if (cmbQueryType != null)
{
break;
}
}
else if (strSection == "Name")
{
TextBox txtName = row.Cells[i].FindControl("txtName") as TextBox;
if (txtName != null)
{
break;
}
}
}
return intVal;
}
根据我的理解，直接来自 Microsoft 页面：使用指定的 id 参数搜索服务器控件的 当前 命名容器。
所以我的问题是，为什么这个看似找到控件的列是错误的？我无法对特定列进行硬编码，因为显示的列因数据源而异。
根据请求，网格视图：
<TDWeb:PageGridView SkinID="pagegrid" EmptyDataText="No unmatched parameters." ID="gvUnmatched" runat="server" AllowSorting="True"
OnSorting="gvUnmatched_Sorting" AutoGenerateColumns="False" OnRowDataBound="gvUnmatched_RowDatabound" OnDataBound="gvUnmatched_DataBound"
OnPreRender="gvUnmatched_PreRender" OnPageIndexChanging="OnFilterUnmatched" DataKeyNames="InternalName"
ShowFooter="true" OnPageSizeChanged="gvUnmatched_PageSizeChanged">
<Columns>
<asp:TemplateField runat="server" ItemStyle-CssClass="c" FooterStyle-CssClass="c">
<HeaderTemplate>
<asp:Label runat="server" Text="Add" />
<asp:CheckBox runat="server" ID="ckbAddAll" />
</HeaderTemplate>
<ItemTemplate>
<asp:CheckBox runat="server" ID="ckbAdd" EnableViewState="true" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" ItemStyle-CssClass="c">
<HeaderTemplate>
<asp:Label runat="server" Text="Ignore" />
<asp:CheckBox runat="server" ID="ckbIgnoreAll" />
</HeaderTemplate>
<ItemTemplate>
<asp:CheckBox runat="server" ID="ckbIgnore" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Name" SortExpression="Name" ItemStyle-CssClass="l">
<HeaderTemplate>
<asp:LinkButton runat="server" Text="Name" CommandName="Sort" CommandArgument="Name" />
<td:HelperBox ID="HelperBox5" runat="server" ToolTipText="Set the Name for this parameter. This value must be unique to the CAN Bus or ECU and is the value used throughout the DAP system to reference this parameter." />
</HeaderTemplate>
<ItemTemplate>
<asp:TextBox runat="server" ID="txtName" Width="250" MaxLength="256" style="background-color:inherit" Text='<%# Bind("Name") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" ItemStyle-CssClass="l" SortExpression="Description">
<HeaderTemplate>
<asp:LinkButton runat="server" Text="Description" CommandName="Sort" CommandArgument="Description" />
<td:HelperBox ID="HelperBox4" runat="server" ToolTipText="Set the Description for this parameter. This value is for informational purposes only. Not required." />
</HeaderTemplate>
<ItemTemplate>
<asp:TextBox runat="server" ID="txtDescription" Width="175" MaxLength="500"
TextMode="multiline" style="background-color:inherit" Text='<%# Bind("Description") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Length (bits)" SortExpression="LengthBits" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtSizeBits" Text='<%# (int)Eval("LengthBits") + (int)Eval("LengthBytes") * 8 %>' style="background-color:inherit" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="SourceAddress" HeaderText="SA" SortExpression="Sources" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtSources" Text='<%# Eval("SourceString") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="ID" HeaderText="ID/Address" SortExpression="IDorAddress" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtIDorAddress" Text='<%# Eval("IDorAddress") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Data Type" SortExpression="Datatype" ItemStyle-CssClass="l">
<ItemTemplate>
<asp:Label runat="server" ID="txtDatatype" Text='<%# Bind("Datatype") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="QueryRate" ItemStyle-CssClass="r" SortExpression="QueryRate" HeaderText="Query Rate">
<HeaderTemplate>
<asp:Label runat="server" Text="Rate" />
<td:HelperBox ID="HelperBox9" runat="server" ToolTipText="Set the Query Type and Rate for this parameter (if applicable). If set, this value overrides the default Query set below." />
</HeaderTemplate>
<ItemTemplate>
<asp:Label runat="server" ID="lblCANRate" Text='<%# Eval("QueryRateString", "{0} s") %>' Visible='<%# m_SelectedFile.ImportType == App_Code.DAPConfig.ParameterFileImport.EImportType.CANDBC || (m_SelectedFile.ImportType == App_Code.DAPConfig.ParameterFileImport.EImportType.J1939DBC && ((int)Eval("QueryRate")) > 0) %>' />
<asp:DropDownList runat="server" ID="cmbQueryType" style="background-color:inherit" Visible='<%# m_SelectedFile.ImportType != App_Code.DAPConfig.ParameterFileImport.EImportType.CANDBC && (m_SelectedFile.ImportType != App_Code.DAPConfig.ParameterFileImport.EImportType.J1939DBC || (int)Eval("QueryRate") <= 0) %>' />
<asp:Panel runat="server" id="pnlRate" style="display:none" ><asp:TextBox runat="server" ID="txtRate" Width="50" MaxLength="6" style="background-color:inherit" />s</asp:Panel>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Category" ItemStyle-CssClass="l">
<HeaderTemplate>
<asp:Label runat="server" Text="Category" />
<td:HelperBox ID="HelperBox10" runat="server" ToolTipText="Set the Category with which to group this parameter, or create a new category." />
</HeaderTemplate>
<ItemTemplate>
<asp:DropDownList runat="server" ID="cmbCategory" style="background-color:inherit" >
<asp:ListItem Value="_New_" Text="Add New..." />
</asp:DropDownList>
<br />
<asp:TextBox Width="100" MaxLength="50" runat="server" ID="txtCategory" style="display:none;background-color:inherit" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</TDWeb:PageGridView>
如果您知道要查找的控件的 ID，则无需指定单元格。你可以通过查看整行找到它。
DropDownList cmbQueryType = row.FindControl("cmbQueryType") as DropDownList
这样可以避免单元格索引不正确的问题。
ok - 结果调用 row.cells(0).FindControl("") 等同于调用 row.FindControl("")，因为 FindControl() 在当前 NamingContainer 中运行。并且给定行中的所有单元格都具有相同的 NamingContainer，特别是 {System.Web.UI.WebControls.GridViewRow}
如果您只需要确定给定控件的列索引，请试试这个（请原谅 VB）：
Public Function getCellIndexByName(ByVal row As GridViewRow, ByVal ColumnName As String) As Integer
For ci As Integer = 0 To row.Cells.Count - 1
If CType(row.Cells(ci), DataControlFieldCell).ContainingField.ToString() = ColumnName Then
Return ci
End If
Next
Return -1
End Function
我有一个我编写的函数，您传入 gridview 行，以及您试图定位的控件类型。它按预期找到了控件，但是，它在错误的单元格中找到了它。
protected int GetCell(GridViewRow row, string strSection)
{
int intVal = 0;
for (int i = 0; i < row.Cells.Count; i++)
{
intVal = i;
if (strSection == "QueryRate")
{
DropDownList cmbQueryType = row.Cells[i].FindControl("cmbQueryType") as DropDownList;
if (cmbQueryType != null)
{
break;
}
}
else if (strSection == "Name")
{
TextBox txtName = row.Cells[i].FindControl("txtName") as TextBox;
if (txtName != null)
{
break;
}
}
}
return intVal;
}
根据我的理解，直接来自 Microsoft 页面：使用指定的 id 参数搜索服务器控件的 当前 命名容器。
所以我的问题是，为什么这个看似找到控件的列是错误的？我无法对特定列进行硬编码，因为显示的列因数据源而异。
根据请求，网格视图：
<TDWeb:PageGridView SkinID="pagegrid" EmptyDataText="No unmatched parameters." ID="gvUnmatched" runat="server" AllowSorting="True"
OnSorting="gvUnmatched_Sorting" AutoGenerateColumns="False" OnRowDataBound="gvUnmatched_RowDatabound" OnDataBound="gvUnmatched_DataBound"
OnPreRender="gvUnmatched_PreRender" OnPageIndexChanging="OnFilterUnmatched" DataKeyNames="InternalName"
ShowFooter="true" OnPageSizeChanged="gvUnmatched_PageSizeChanged">
<Columns>
<asp:TemplateField runat="server" ItemStyle-CssClass="c" FooterStyle-CssClass="c">
<HeaderTemplate>
<asp:Label runat="server" Text="Add" />
<asp:CheckBox runat="server" ID="ckbAddAll" />
</HeaderTemplate>
<ItemTemplate>
<asp:CheckBox runat="server" ID="ckbAdd" EnableViewState="true" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" ItemStyle-CssClass="c">
<HeaderTemplate>
<asp:Label runat="server" Text="Ignore" />
<asp:CheckBox runat="server" ID="ckbIgnoreAll" />
</HeaderTemplate>
<ItemTemplate>
<asp:CheckBox runat="server" ID="ckbIgnore" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Name" SortExpression="Name" ItemStyle-CssClass="l">
<HeaderTemplate>
<asp:LinkButton runat="server" Text="Name" CommandName="Sort" CommandArgument="Name" />
<td:HelperBox ID="HelperBox5" runat="server" ToolTipText="Set the Name for this parameter. This value must be unique to the CAN Bus or ECU and is the value used throughout the DAP system to reference this parameter." />
</HeaderTemplate>
<ItemTemplate>
<asp:TextBox runat="server" ID="txtName" Width="250" MaxLength="256" style="background-color:inherit" Text='<%# Bind("Name") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" ItemStyle-CssClass="l" SortExpression="Description">
<HeaderTemplate>
<asp:LinkButton runat="server" Text="Description" CommandName="Sort" CommandArgument="Description" />
<td:HelperBox ID="HelperBox4" runat="server" ToolTipText="Set the Description for this parameter. This value is for informational purposes only. Not required." />
</HeaderTemplate>
<ItemTemplate>
<asp:TextBox runat="server" ID="txtDescription" Width="175" MaxLength="500"
TextMode="multiline" style="background-color:inherit" Text='<%# Bind("Description") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Length (bits)" SortExpression="LengthBits" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtSizeBits" Text='<%# (int)Eval("LengthBits") + (int)Eval("LengthBytes") * 8 %>' style="background-color:inherit" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="SourceAddress" HeaderText="SA" SortExpression="Sources" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtSources" Text='<%# Eval("SourceString") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="ID" HeaderText="ID/Address" SortExpression="IDorAddress" ItemStyle-CssClass="r">
<ItemTemplate>
<asp:Label runat="server" ID="txtIDorAddress" Text='<%# Eval("IDorAddress") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Data Type" SortExpression="Datatype" ItemStyle-CssClass="l">
<ItemTemplate>
<asp:Label runat="server" ID="txtDatatype" Text='<%# Bind("Datatype") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" AccessibleHeaderText="QueryRate" ItemStyle-CssClass="r" SortExpression="QueryRate" HeaderText="Query Rate">
<HeaderTemplate>
<asp:Label runat="server" Text="Rate" />
<td:HelperBox ID="HelperBox9" runat="server" ToolTipText="Set the Query Type and Rate for this parameter (if applicable). If set, this value overrides the default Query set below." />
</HeaderTemplate>
<ItemTemplate>
<asp:Label runat="server" ID="lblCANRate" Text='<%# Eval("QueryRateString", "{0} s") %>' Visible='<%# m_SelectedFile.ImportType == App_Code.DAPConfig.ParameterFileImport.EImportType.CANDBC || (m_SelectedFile.ImportType == App_Code.DAPConfig.ParameterFileImport.EImportType.J1939DBC && ((int)Eval("QueryRate")) > 0) %>' />
<asp:DropDownList runat="server" ID="cmbQueryType" style="background-color:inherit" Visible='<%# m_SelectedFile.ImportType != App_Code.DAPConfig.ParameterFileImport.EImportType.CANDBC && (m_SelectedFile.ImportType != App_Code.DAPConfig.ParameterFileImport.EImportType.J1939DBC || (int)Eval("QueryRate") <= 0) %>' />
<asp:Panel runat="server" id="pnlRate" style="display:none" ><asp:TextBox runat="server" ID="txtRate" Width="50" MaxLength="6" style="background-color:inherit" />s</asp:Panel>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField runat="server" HeaderText="Category" ItemStyle-CssClass="l">
<HeaderTemplate>
<asp:Label runat="server" Text="Category" />
<td:HelperBox ID="HelperBox10" runat="server" ToolTipText="Set the Category with which to group this parameter, or create a new category." />
</HeaderTemplate>
<ItemTemplate>
<asp:DropDownList runat="server" ID="cmbCategory" style="background-color:inherit" >
<asp:ListItem Value="_New_" Text="Add New..." />
</asp:DropDownList>
<br />
<asp:TextBox Width="100" MaxLength="50" runat="server" ID="txtCategory" style="display:none;background-color:inherit" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</TDWeb:PageGridView>
如果您知道要查找的控件的 ID，则无需指定单元格。你可以通过查看整行找到它。
DropDownList cmbQueryType = row.FindControl("cmbQueryType") as DropDownList
这样可以避免单元格索引不正确的问题。
ok - 结果调用 row.cells(0).FindControl("") 等同于调用 row.FindControl("")，因为 FindControl() 在当前 NamingContainer 中运行。并且给定行中的所有单元格都具有相同的 NamingContainer，特别是 {System.Web.UI.WebControls.GridViewRow}
如果您只需要确定给定控件的列索引，请试试这个（请原谅 VB）：
Public Function getCellIndexByName(ByVal row As GridViewRow, ByVal ColumnName As String) As Integer
For ci As Integer = 0 To row.Cells.Count - 1
If CType(row.Cells(ci), DataControlFieldCell).ContainingField.ToString() = ColumnName Then
Return ci
End If
Next
Return -1
End Function