Select all checkboxes in DetailsView items.

Question

Note. I updated the code for this question to make the example clearer and uses the example code provided by Karl Anderson below. I am also open to other ways of getting what I need to complete.

I am creating a form containing several checkboxes that may or may not be used for each request. I am trying to create a button below these checkboxes in the DetailsView grid, which will check (as opposed to a button that will check and uncheck), if it becomes necessary to check them all. As you can see from the code below, there are several text fields / BoundFields surrounding the checkboxes that contain various types of information for this form. The form without the additional complexity of the “check all flags” button works without any problems in the external interface and when writing to the database.

Using the code below the current obstacle that I am facing is not only that the button allows you to only check all the checkboxes at once, but skip this error when loading the page:

It is not possible to convert the type "System.Web.UI.WebControls.TableCell" to "System.Web.UI.WebControls.CheckBox" through a link conversion, box conversion, unboxing conversion, conversion conversion or null type conversion

From my research on similar (but not exact) errors, I need to convert the checkboxes to another form. I’ve never come across this scenario before, and I stretch my hair not only in search of educational links, but also in some kind of pointer on how to allow not only part of the conversion, but also accurate and current (over the past few years) links to how I can solve a big problem with a button by correctly checking all 19 checkboxes.

What am I doing wrong here, and is this the right way to get the results that I want to do DetailsView? I would not only like to learn how to solve this, but also to study the theory / logic behind this task so that I can study it correctly.

aspx code.

(Note some cosmetic code for the details view has been omitted) <%@ Page Title="Test Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeFile="form2.aspx.cs" Inherits="form2" %> <asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" Runat="Server"> </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="FeaturedContent" Runat="Server"> </asp:Content> <asp:Content ID="Content3" ContentPlaceHolderID="MainContent" Runat="Server"> <asp:DetailsView ID="DetailsView" runat="server" AutoGenerateColumns="False" CellPadding="4" DataSourceID="SqlDataSource1" ForeColor="#333333" GridLines="None"> <AlternatingRowStyle BackColor="White" /> <insert asp cosmetic gobbledy gook here> <Fields> <asp:BoundField DataField="Field_1" HeaderText="Ticket Number" SortExpression="Field_1" /> <asp:BoundField DataField="Field 2" HeaderText="Field 2" SortExpression="Field_2" /> <asp:BoundField DataField="Field_3" HeaderText="Field 3" SortExpression="Field_3" /> <asp:BoundField DataField="Field_4" HeaderText="Field 4" SortExpression="Field_4" /> <asp:BoundField DataField="Field_5" HeaderText="Field 5" SortExpression="Field_5" /> <asp:BoundField DataField="Field_6" HeaderText="Field 6" SortExpression="Field_6" /> <asp:BoundField DataField="Field_7" HeaderText="Field 7" SortExpression="Field_7" /> <asp:BoundField DataField="Field_8" HeaderText="Field 8" SortExpression="Field_8" /> <asp:BoundField DataField="Field_9" HeaderText="Field 9" SortExpression="Field_9" /> <asp:BoundField DataField="Field_10" HeaderText="Field 10" SortExpression="Field_10" /> <asp:CheckBoxField DataField="Check_Box_1" HeaderText="Check Box 1" SortExpression="Check_Box_1" /> <asp:CheckBoxField DataField="Check_Box_2" HeaderText="Check Box 2" SortExpression="Check_Box_2" /> <asp:CheckBoxField DataField="Check_Box_3" HeaderText="Check Box 3" SortExpression="Check_Box_3" /> <asp:CheckBoxField DataField="Check_Box_4" HeaderText="Check Box 4" SortExpression="Check_Box_4" /> <asp:CheckBoxField DataField="Check_Box_5" HeaderText="Check Box 5" SortExpression="Check_Box_5" /> <asp:CheckBoxField DataField="Check_Box_6" HeaderText="Check Box 6" SortExpression="Check_Box_6" /> <asp:CheckBoxField DataField="Check_Box_7" HeaderText="Check Box 7" SortExpression="Check_Box_7" /> <asp:CheckBoxField DataField="Check_Box_8" HeaderText="Check Box 8" SortExpression="Check_Box_8" /> <asp:CheckBoxField DataField="Check_Box_9" HeaderText="Check Box 9" SortExpression="Check_Box_9" /> <asp:CheckBoxField DataField="Check_Box_10" HeaderText="Check Box 10" SortExpression="Check_Box_10" /> <asp:CheckBoxField DataField="Check_Box_11" HeaderText="Check Box 11" SortExpression="Check_Box_11" /> <asp:CheckBoxField DataField="Check_Box_12" HeaderText="Check Box 12" SortExpression="Check_Box_12" /> <asp:CheckBoxField DataField="Check_Box_13" HeaderText="Check Box 13" SortExpression="Check_Box_13" /> <asp:CheckBoxField DataField="Check_Box_14" HeaderText="Check Box 14" SortExpression="Check_Box_14" /> <asp:CheckBoxField DataField="Check_Box_15" HeaderText="Check Box 15" SortExpression="Check_Box_15" /> <asp:CheckBoxField DataField="Check_Box_16" HeaderText="Check Box 16" SortExpression="Check_Box_16" /> <asp:CheckBoxField DataField="Check_Box_17" HeaderText="Check Box 17" SortExpression="Check_Box_17" /> <asp:CheckBoxField DataField="Check_Box_18" HeaderText="Check Box 18" SortExpression="Check_Box_18" /> <asp:CheckBoxField DataField="Check_Box_19" HeaderText="Check Box 19" SortExpression="Check_Box_19" /> <asp:ButtonField ButtonType="Button" CommandName="btnSelectAll" Text="Select/Check All Servers" <asp:BoundField DataField="Field_11" HeaderText="Field 11" SortExpression="Field_11" /> <asp:BoundField DataField="Field_12" HeaderText="Field 12" SortExpression="Field_12" /> <asp:BoundField DataField="Field_13" HeaderText="Field 13" SortExpression="Field_13" /> <asp:CommandField ButtonType="Button" NewText="CreateRecord" ShowInsertButton="True" /> </Fields> <more asp non essential cosmetic gobbledy gook> </asp:DetailsView> <asp:SqlDataSource ID="SqlDataSource1" ConnectionString="<%$ ConnectionStrings:test_form_connect %>" runat="server" InsertCommand="INSERT INTO [test].[detailsview_test_form] ([Field_1], [Field_2], [Field_3], [Field_4], [Field_5], [Field_6], [Field_7], [Field_8], [Field_9], [Field_10], [Check_Box_1], [Check_Box_2], [Check_Box_3], [Check_Box_4], [Check_Box_5], [Check_Box_6], [Check_Box_7], [Check_Box_8], [Check_Box_9], [Check_Box_10], [Check_Box_11], [Check_Box_12], [Check_Box_13], [Check_Box_14], [Check_Box_15], [Check_Box_16], [Check_Box_17], [Check_Box_18], [Check_Box_19], [Field_11], [Field_12], [Field_13]) VALUES (@Field_1, @Field_2, @Field_3, @Field_4, @Field_5, @Field_6, @Field_7, @Field_8, @Field_9, @Field_10, @Check_Box_1, @Check_Box_2, @Check_Box_3, @Check_Box_4, @Check_Box_5, @Check_Box_6, @Check_Box_7, @Check_Box_8, @Check_Box_9, @Check_Box_10, @Check_Box_11, @Check_Box_12, @Check_Box_13, @Check_Box_14, @Check_Box_15, @Check_Box_16, @Check_Box_17, @Check_Box_18, @Check_Box_19, @Field_11, @Field_12, @Field_13) "> <InsertParameters> <asp:Parameter Name="Field_1" /> <asp:Parameter Name="Field_2" /> <asp:Parameter Name="Field_3" /> <asp:Parameter Name="Field_4" /> <asp:Parameter Name="Field_5" /> <asp:Parameter Name="Field_6" /> <asp:Parameter Name="Field_7" /> <asp:Parameter Name="Field_8" /> <asp:Parameter Name="Field_9" /> <asp:Parameter Name="Field_10" /> <asp:Parameter Name="Check_Box_1" /> <asp:Parameter Name="Check_Box_2" /> <asp:Parameter Name="Check_Box_3" /> <asp:Parameter Name="Check_Box_4" /> <asp:Parameter Name="Check_Box_5" /> <asp:Parameter Name="Check_Box_6" /> <asp:Parameter Name="Check_Box_7" /> <asp:Parameter Name="Check_Box_8" /> <asp:Parameter Name="Check_Box_9" /> <asp:Parameter Name="Check_Box_10" /> <asp:Parameter Name="Check_Box_11" /> <asp:Parameter Name="Check_Box_12" /> <asp:Parameter Name="Check_Box_13" /> <asp:Parameter Name="Check_Box_14" /> <asp:Parameter Name="Check_Box_15" /> <asp:Parameter Name="Check_Box_16" /> <asp:Parameter Name="Check_Box_17" /> <asp:Parameter Name="Check_Box_18" /> <asp:Parameter Name="Check_Box_19" /> <asp:Parameter Name="Field_11" /> <asp:Parameter Name="Field_12" /> <asp:Parameter Name="Field_13" /> </InsertParameters> </asp:SqlDataSource> </asp:Content> 

..... and cs code:

 using System; using System.Configuration; using System.Collections; using System.Data; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; public partial class form2 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void DetailsView1_ItemCommand(Object sender, DetailsViewCommandEventArgs e) { foreach (Details if (e.CommandName == "btnSelectAll") { DetailsViewRow row = DetailsView1.Rows[9]; (row.Cells[10] as CheckBox).Checked = true; DetailsViewRow row1 = DetailsView1.Rows[10]; (row1.Cells[11] as CheckBox).Checked = true; DetailsViewRow row2 = DetailsView1.Rows[11]; (row.Cells[12] as CheckBox).Checked = true; DetailsViewRow row3 = DetailsView1.Rows[12]; (row.Cells[13] as CheckBox).Checked = true; DetailsViewRow row4 = DetailsView1.Rows[13]; (row.Cells[14] as CheckBox).Checked = true; DetailsViewRow row5 = DetailsView1.Rows[14]; (row.Cells[15] as CheckBox).Checked = true; DetailsViewRow row6 = DetailsView1.Rows[15]; (row.Cells[16] as CheckBox).Checked = true; DetailsViewRow row7 = DetailsView1.Rows[16]; (row.Cells[17] as CheckBox).Checked = true; DetailsViewRow row8 = DetailsView1.Rows[17]; (row.Cells[18] as CheckBox).Checked = true; DetailsViewRow row9 = DetailsView1.Rows[18]; (row.Cells[19] as CheckBox).Checked = true; DetailsViewRow row10 = DetailsView1.Rows[19]; (row.Cells[20] as CheckBox).Checked = true; DetailsViewRow row11 = DetailsView1.Rows[20]; (row.Cells[21] as CheckBox).Checked = true; DetailsViewRow row12 = DetailsView1.Rows[21]; (row.Cells[22] as CheckBox).Checked = true; DetailsViewRow row13 = DetailsView1.Rows[22]; (row.Cells[23] as CheckBox).Checked = true; DetailsViewRow row14 = DetailsView1.Rows[23]; (row.Cells[24] as CheckBox).Checked = true; DetailsViewRow row15 = DetailsView1.Rows[24]; (row.Cells[25] as CheckBox).Checked = true; DetailsViewRow row16 = DetailsView1.Rows[25]; (row.Cells[26] as CheckBox).Checked = true; DetailsViewRow row17 = DetailsView1.Rows[26]; (row.Cells[27] as CheckBox).Checked = true; DetailsViewRow row18 = DetailsView1.Rows[27]; (row.Cells[28] as CheckBox).Checked = true; DetailsViewRow row19 = DetailsView1.Rows[28]; (row.Cells[29] as CheckBox).Checked = true; } } } 

Answer 1

The reason you get "System.Web.UI.WebControls.CheckBox" through a link conversion, box conversion, unbox conversion, conversion conversion, or null type conversion "is because you are trying to pass a cell to a CheckBox.

Notice that I found the CheckBox control inside the Rows CellCollection cell control.

The following is an example of test code that works:

the form:

  <asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateColumns="False" CellPadding="4" ForeColor="#333333" GridLines="None" OnItemCommand="DetailsView1_ItemCommand"> <AlternatingRowStyle BackColor="White" /> <Fields> <asp:ButtonField ButtonType="Button" CommandName="btnSelectAll" Text="Select/Check All Servers" /> <asp:ButtonField ButtonType="Button" CommandName="btnEdit" Text="Edit" /> <asp:ButtonField ButtonType="Button" CommandName="btnCancel" Text="Cancel" /> <asp:ButtonField ButtonType="Button" CommandName="btnSave" Text="Save" /> <asp:CommandField ButtonType="Button" NewText="CreateRecord" ShowInsertButton="True" /> </Fields> </asp:DetailsView> 

Code for:

  DataTable m_table = null; public DataTable table { get { if (ViewState["m_table"] != null) return (DataTable)ViewState["m_table"]; else return null; } set { ViewState["m_table"] = value; } } public static T FindControl<T>(ControlCollection controls) { for (int i = 0; i < controls.Count; i++) { if (controls[i] is T) return (T)(object)controls[i]; } return default(T); } protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { table = new DataTable(); DataColumn col1 = new DataColumn("Field_1"); DataColumn col11 = new DataColumn("Check_Box_1"); DataColumn col12 = new DataColumn("Check_Box_2"); DataColumn col13 = new DataColumn("Check_Box_3"); col1.DataType = System.Type.GetType("System.String"); col11.DataType = System.Type.GetType("System.Boolean"); col12.DataType = System.Type.GetType("System.Boolean"); col13.DataType = System.Type.GetType("System.Boolean"); table.Columns.Add(col1); table.Columns.Add(col11); table.Columns.Add(col12); table.Columns.Add(col13); DataRow row = table.NewRow(); row[col1] = "1"; row[col11] = false; row[col12] = false; row[col13] = false; table.Rows.Add(row); DetailsView1.DataSource = table; DetailsView1.DataBind(); } } protected void DetailsView1_ItemCommand(Object sender, DetailsViewCommandEventArgs e) { if (e.CommandName == "btnSelectAll") { foreach (DetailsViewRow row in DetailsView1.Rows) { for (int i = 0; i < row.Cells.Count; i++) { CheckBox cb = FindControl<CheckBox>(row.Cells[i].Controls); if (cb != null) { cb.Checked = true; } } } } if (e.CommandName == "btnSave") { int j = 0; foreach (DetailsViewRow row in DetailsView1.Rows) { for (int i = 0; i < row.Cells.Count; i++) { TextBox tb = FindControl<TextBox>(row.Cells[i].Controls); if (tb != null) { table.Rows[0][j] = tb.Text; } CheckBox cb = FindControl<CheckBox>(row.Cells[i].Controls); if (cb != null) { table.Rows[0][j] = cb.Checked; } } j++; } DetailsView1.ChangeMode(DetailsViewMode.ReadOnly); DetailsView1.DataSource = table; DetailsView1.DataBind(); } if (e.CommandName == "btnEdit") { DetailsView1.ChangeMode(DetailsViewMode.Edit); DetailsView1.DataSource = table; DetailsView1.DataBind(); } if (e.CommandName == "btnCancel") { DetailsView1.ChangeMode(DetailsViewMode.ReadOnly); DetailsView1.DataSource = table; DetailsView1.DataBind(); } } 

Answer 2

This is not tested, but should work, so try the following:

 protected void DetailsView1_ItemCommand(Object sender, DetailsViewCommandEventArgs e) { // Use the CommandName property to determine which button // was clicked. if (e.CommandName == "btnSelectAll") { // You may need to tweak this as I almost never use DetailsView, but the concept should work // Check the Apples checkbox // Apples is the first row (index 0) and second cell (index 1) DetailsViewRow row = DetailsView1.Rows[0]; (row.Cells[1] as CheckBox).Checked = true; // Check the Oranges checkbox // Apples is the second row (index 1) and second cell (index 1) DetailsViewRow row = DetailsView1.Rows[1]; (row.Cells[1] as CheckBox).Checked = true; // Keep moving through the rows... } } 

Answer 3

try using the client side of the script as

 $(".btnClass").click(function(){ $(".chkBoxClass").attr("checked", "checked"); }); 

where btnClass is the class for the button, and chkBoxClass is the common class for flags.

Answer 4

If you set a breakpoint in code like row.Cells[0] and look at the Controls property (either in the Quick Watch window or in one of the other debug windows), you can find the corresponding CheckBoxes and find out how to go to them from each cell .

HOWEVER , this should hit you as a really bad idea. Your code is now closely related to the structure of the page. It will be very difficult for you to keep going forward, and anyone working on this project will probably spend a lot of time trying to figure it out. This code needs to be thrown away.

If you need to have this many fields on the form, consider separating these fields on a separate page in full and actually create the fields separately on the page itself. You might think that this will take longer for users, but to be honest, this form has 13 parameters and 19 CheckBoxes . This is a complex form that requires special attention and attention.

Finally, the time that you (and other developers) save when making improvements to this page and fixing bugs will quickly return users.

Answer 5

Based on Karl Anderson's answer:

 protected void DetailsView1_ItemCommand(Object sender, DetailsViewCommandEventArgs e) { if (e.CommandName == "btnSelectAll") { foreach (DetailsViewRow row in DetailsView1.Rows) { (row.Cells[1].Controls[0] as CheckBox).Checked = true; } } } 

I'm not sure if this fixes everything, but it needs to be pulled into a loop, and I believe that Controls[0] will provide a handle to this flag.

Answer 6

I would try:

 protected void DetailsView1_ItemCommand(Object sender, DetailsViewCommandEventArgs e) { if (e.CommandName == "btnSelectAll") { var controls = new Stack<Control>(); controls.Push(DetailsView1); while (controls.Count > 0) { var control = controls.Pop(); var checkbox = control as CheckBox; if (checkbox != null) { checkbox.Checked = true; } foreach (Control childControl in control.Controls) { controls.Push(childControl); } } } } 

Recurrent controls for children work even on different types of controls.

Answer 7

Ok, so all you have to do to open this checkbox is change this line:

 (row.Cells[10] as CheckBox).Checked = true; 

to this line:

 (row.Cells[10].Controls[0] as CheckBox).Checked = true; 

TableCell contains a set of controls that are actually used to render the user interface. In the case of CheckBoxField first control in the collection is CheckBox .

Now, to make this code a little more scalable, I could do this:

 if (e.CommandName == "btnSelectAll") { for (int i = 9; i < 29; i++) { DetailsViewRow row = DetailsView1.Rows[i]; (row.Cells[i + 1].Controls[0] as CheckBox).Checked = true; }