Enable Disable CheckBox when TextBox in empty in ASP.Net GridView using C# and VB.Net

Hi ihechi,

Please refer below sample code.

You need to assign the TextChange event to the txtspouseaddress TextBox and check the condition with both the TextBoxes.

Database

I have made use of the following table Customers with the schema as follows.

I have already inserted few records in the table.

You can download the database table SQL by clicking the download link below.

Download SQL file

HTML

<asp:GridView ID="grvspouse" RowStyle-Wrap="false" GridLines="None" CssClass="responsiveTable1"
    runat="server" ShowFooter="true" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="CustomerId" Visible="false" HeaderText="Row Number" />
        <asp:TemplateField HeaderText="Name">
            <HeaderStyle HorizontalAlign="Left" />
            <ItemTemplate>
                <asp:TextBox ID="txtName" Text='<%# Eval("Name") %>' placeholder="Name...(e.g, Jane Doe)"
                    runat="server" Style="width: 375px;" class="form-control" AutoPostBack="true"
                    OnTextChanged="txtspousename_TextChanged"></asp:TextBox><br />
                <asp:CheckBox ID="spouseDetails" ClientIDMode="Static" runat="server" Checked="false"
                    AutoPostBack="true" OnCheckedChanged="SpouseCheckChanged" /><span style="color: #ff0000">*Check
                        this box if N/A</span>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Address">
            <ItemStyle HorizontalAlign="Left"></ItemStyle>
            <ItemTemplate>
                <asp:TextBox ID="txtAddress" Text='<%# Eval("Country") %>' placeholder="Address..."
                    runat="server" Style="width: 375px;" class="form-control" AutoPostBack="true"
                    OnTextChanged="txtspousename_TextChanged"></asp:TextBox><br />
                <br />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

Namespaces

CS

using System.Data;
using System.Configuration;
using System.Data.SqlClient;

VB.Net

Imports System.Data
Imports System.Configuration
Imports System.Data.SqlClient

Code

CS

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        string query = "SELECT *  FROM Customers";
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter(query, con))
            {
                using (DataTable dt = new DataTable())
                {
                    sda.Fill(dt);
                    grvspouse.DataSource = dt;
                    grvspouse.DataBind();
                }
            }
        }
    }
}

protected void txtspousename_TextChanged(object sender, EventArgs e)
{
    GridViewRow row = (sender as TextBox).NamingContainer as GridViewRow;
    TextBox spousename = row.FindControl("txtName") as TextBox;
    TextBox spouseaddress = row.FindControl("txtAddress") as TextBox;
    CheckBox spouseSelect = row.FindControl("spouseDetails") as CheckBox;
    if (spousename.Text.Length > 0 && spouseaddress.Text.Length > 0)
        spouseSelect.Enabled = false;
    else
        spouseSelect.Enabled = true;
}

protected void SpouseCheckChanged(object sender, EventArgs e)
{
    GridViewRow row = (sender as CheckBox).NamingContainer as GridViewRow;
    TextBox spousename = row.FindControl("txtName") as TextBox;
    TextBox spouseaddress = row.FindControl("txtAddress") as TextBox;
    CheckBox spouseSelect = row.FindControl("spouseDetails") as CheckBox;
    if (!spouseSelect.Checked)
    {
        spousename.Enabled = true;
        spouseaddress.Enabled = true;
    }
    else
    {
        spousename.Enabled = false;
        spouseaddress.Enabled = false;
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
        Dim query As String = "SELECT *  FROM Customers"
        Using con As SqlConnection = New SqlConnection(constr)
            Using sda As SqlDataAdapter = New SqlDataAdapter(query, con)
                Using dt As DataTable = New DataTable()
                    sda.Fill(dt)
                    grvspouse.DataSource = dt
                    grvspouse.DataBind()
                End Using
            End Using
        End Using
    End If
End Sub

Protected Sub txtspousename_TextChanged(sender As Object, e As EventArgs)
    Dim row As GridViewRow = TryCast((TryCast(sender, TextBox)).NamingContainer, GridViewRow)
    Dim spousename As TextBox = TryCast(row.FindControl("txtName"), TextBox)
    Dim spouseaddress As TextBox = TryCast(row.FindControl("txtAddress"), TextBox)
    Dim spouseSelect As CheckBox = TryCast(row.FindControl("spouseDetails"), CheckBox)
    If spousename.Text.Length > 0 AndAlso spouseaddress.Text.Length > 0 Then
        spouseSelect.Enabled = False
    Else
        spouseSelect.Enabled = True
    End If
End Sub

Protected Sub SpouseCheckChanged(ByVal sender As Object, ByVal e As EventArgs)
    Dim row As GridViewRow = TryCast((TryCast(sender, CheckBox)).NamingContainer, GridViewRow)
    Dim spousename As TextBox = TryCast(row.FindControl("txtName"), TextBox)
    Dim spouseaddress As TextBox = TryCast(row.FindControl("txtAddress"), TextBox)
    Dim spouseSelect As CheckBox = TryCast(row.FindControl("spouseDetails"), CheckBox)
    If Not spouseSelect.Checked Then
        spousename.Enabled = True
        spouseaddress.Enabled = True
    Else
        spousename.Enabled = False
        spouseaddress.Enabled = False
    End If
End Sub

Screenshot