I have below list view , how can i hide column by code behind ?

    <asp:ListView ID="AuditLogListView" runat="server" OnItemCreated="AuditLogListView_ItemCreated">
    <LayoutTemplate>
        <table class="table table-striped table-bordered small">
            <tr class="table-secondary">
    <th id="BlockHeader" runat="server" style="white-space: normal;">
                <asp:Literal ID="BlockHeaderLiteral" runat="server" Text="<%$ Resources:AppResources, AuditInformationBlockHeader %>" />
            </th>
        </tr>
            <asp:PlaceHolder runat="server" ID="ItemPlaceholder"></asp:PlaceHolder>
        </table>
    
    </LayoutTemplate>
<ItemTemplate>            
    <tr>
        <td id="BlockStatus" runat="server">
            <%# Eval("BlockStatus")%>
        </td>
    </tr>
</ItemTemplate>

After binding data with list view i tried below code behind but with this header text only hide but column still can still visible

if (groupOrBlockValue == 'W')

        {
            AuditLogListView.FindControl("BlockHeader").Visible = false;
            AuditLogListView.FindControl("BlockHeaderLiteral").Visible = false;
           //AuditLogListView.FindControl("BlockStatus").Visible = false;
        }

CodePudding user response：

Missing part of the list view?

With this:

       <asp:ListView ID="LstMarks" runat="server" DataKeyNames="ID" >
            <ItemTemplate>
                <tr style="">
                    <td><asp:Textbox ID="Course" runat="server" Text='<%# Eval("Course") %>' /></td>
                    <td><asp:Textbox ID="Mark" runat="server" Text='<%# Eval("Mark") %>' Width="30px"/></td>
                    <td>
                        <asp:CheckBox ID="DoneLabs" runat="server" Checked = '<%# Eval("DoneLabs") %>' Width="30px"/>
                    </td>
                </tr>
            </ItemTemplate>
            <LayoutTemplate>
                <table id="itemPlaceholderContainer" runat="server" border="0" class="table">
                    <tr runat="server" style="">
                        <th runat="server" >Course</th>
                        <th runat="server">Mark</th>
                        <th id= "LabW" runat="server" >Completed Lab Work</th>
                    </tr>
                    <tr id="itemPlaceholder" runat="server">
                    </tr>
                </table>
            </LayoutTemplate>
        </asp:ListView>

        <br />
        <br />
        <asp:Button ID="cmdHide" runat="server" Text="Hide Lab check box" OnClick="cmdHide_Click" />

So note in the layout, we added a "id" = LabW - that lets you hide the header.

so, a simple button that would toggle (hide/show) the lvColum, then this works:

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            using (SqlCommand cmdSQL = new SqlCommand("SELECT * from StudentCourses",
                                       new SqlConnection(Properties.Settings.Default.TEST4)))
            {
                cmdSQL.Connection.Open();
                LstMarks.DataSource = cmdSQL.ExecuteReader();
                LstMarks.DataBind();
            }
        }
    }

    protected void cmdHide_Click(object sender, EventArgs e)
    {
        Control ctrHeader = LstMarks.FindControl("LabW");
        ctrHeader.Visible = !ctrHeader.Visible;

        foreach (ListViewItem lvRow in LstMarks.Items)
        {
            CheckBox ckBox = (CheckBox)lvRow.FindControl("DoneLabs");
            ckBox.Visible = !ckBox.Visible;
        }
        
    }

So, we get this:

And clicking on the button, we get this:

And both the values changed - they persist - even when you click again (to toggle and show the hidden columns).

Edit: =====================================================

So, say this markup:

 <asp:ListView ID="AuditLogListView" runat="server"
            OnItemCreated="AuditLogListView_ItemCreated">
    <LayoutTemplate>
        <table class="table table-striped table-bordered small">
            <tr class="table-secondary">
                <th id="BlockHeader" runat="server" style="white-space: normal;">
                <asp:Literal ID="BlockHeaderLiteral" runat="server" Text="Hotel Name" />
            </th>
        </tr>
            <asp:PlaceHolder runat="server" ID="ItemPlaceholder"></asp:PlaceHolder>
        </table>
    </LayoutTemplate>
    <ItemTemplate>            
        <tr>
            <td id="BlockStatus" runat="server">
                <%# Eval("BlockStatus")%>
            </td>
        </tr>
    </ItemTemplate>
</asp:ListView>

        <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />

And code behind button to hide is this:

   protected void Button1_Click(object sender, EventArgs e)
    {
        Control ctrHeader = AuditLogListView.FindControl("BlockHeaderLiteral");
        ctrHeader.Visible = !ctrHeader.Visible;

        foreach (ListViewItem lvRow in AuditLogListView.Items)
        {
            Control BlockStat = (Control)lvRow.FindControl("BlockStatus");
            BlockStat.Visible = !BlockStat.Visible;
        }

    }

CodePudding user response：

At which event have you written this code?

Required this code in the OnDataBound event. And in your code this event missing.

<asp:ListView ID="AuditLogListView" runat="server" OnItemCreated="AuditLogListView_ItemCreated" OnDataBound="AuditLogListView_DataBound"> <asp:Literal ID="BlockHeaderLiteral" runat="server" Text="<%$ Resources:AppResources, AuditInformationBlockHeader %>" /><asp:PlaceHolder runat="server" ID="ItemPlaceholder"></asp:PlaceHolder>

C# Code:

protected void AuditLogListView_DataBound(object sender, EventArgs e) {AuditLogListView.FindControl("BlockHeaderLiteral").Visible = false;}