Validate TextBox in each ASP.Net GridView row using Regular Expression

Hi vijay9471,

Refer below article for validation.

Using ASP.Net RequiredFieldValidator for TextBox inside GridView TemplateField ItemTemplate

Please refer below sample.

HTML

<asp:GridView ID="gvCustomers" runat="server" AutoGenerateColumns="false" OnRowDataBound="OnRowDataBound"
    DataKeyNames="CustomerId">
    <Columns>
        <asp:TemplateField>
            <HeaderTemplate>
                <asp:CheckBox ID="chkAll" runat="server" AutoPostBack="true" OnCheckedChanged="OnCheckedChanged" />
            </HeaderTemplate>
            <ItemTemplate>
                <asp:CheckBox runat="server" AutoPostBack="true" OnCheckedChanged="OnCheckedChanged" />
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Contact Name" ItemStyle-Width="150">
            <ItemTemplate>
                <asp:Label runat="server" Text='<%# Eval("ContactName") %>'></asp:Label>
                <asp:TextBox ID="TextBox1" runat="server" Text='<%# Eval("ContactName") %>' Visible="false"
                    MaxLength="20"></asp:TextBox>
                <asp:RegularExpressionValidator ID="revTextBox1" runat="server" ControlToValidate="TextBox1"
                    ErrorMessage="Please don't enter special characters" ValidationExpression="^[a-zA-Z0-9]+( [a-zA-Z0-9\-])*$"></asp:RegularExpressionValidator>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Country" ItemStyle-Width="150">
            <ItemTemplate>
                <asp:Label ID="lblCountry" runat="server" Text='<%# Eval("Country") %>'></asp:Label>
                <asp:DropDownList ID="ddlCountries" runat="server" Visible="false">
                </asp:DropDownList>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<br />
<asp:Button ID="btnUpdate" runat="server" Text="Update" OnClick="Update" Visible="false" />

Namespaces

C#

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

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        this.BindGrid();
    }
}
private void BindGrid()
{
    SqlCommand cmd = new SqlCommand("SELECT top 10 CustomerId, ContactName, Country FROM Customers");
    gvCustomers.DataSource = this.ExecuteQuery(cmd, "SELECT");
    gvCustomers.DataBind();
}
private DataTable ExecuteQuery(SqlCommand cmd, string action)
{
    string conString = ConfigurationManager.ConnectionStrings["constring"].ConnectionString;
    using (SqlConnection con = new SqlConnection(conString))
    {
        cmd.Connection = con;
        switch (action)
        {
            case "SELECT":
                using (SqlDataAdapter sda = new SqlDataAdapter())
                {
                    sda.SelectCommand = cmd;
                    using (DataTable dt = new DataTable())
                    {
                        sda.Fill(dt);
                        return dt;
                    }
                }
            case "UPDATE":
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
                break;
        }
        return null;
    }
}

protected void Update(object sender, EventArgs e)
{
    foreach (GridViewRow row in gvCustomers.Rows)
    {
        if (row.RowType == DataControlRowType.DataRow)
        {
            bool isChecked = row.Cells[0].Controls.OfType<CheckBox>().FirstOrDefault().Checked;
            if (isChecked)
            {
                SqlCommand cmd = new SqlCommand("UPDATE Customers SET ContactName = @ContactName, Country = @Country WHERE CustomerId = @CustomerId");
                cmd.Parameters.AddWithValue("@ContactName", row.Cells[1].Controls.OfType<TextBox>().FirstOrDefault().Text);
                cmd.Parameters.AddWithValue("@Country", row.Cells[2].Controls.OfType<DropDownList>().FirstOrDefault().SelectedItem.Value);
                cmd.Parameters.AddWithValue("@CustomerId", gvCustomers.DataKeys[row.RowIndex].Value);
                this.ExecuteQuery(cmd, "SELECT");
            }
        }
    }
    btnUpdate.Visible = false;
    this.BindGrid();
}
protected void OnRowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        SqlCommand cmd = new SqlCommand("SELECT DISTINCT(Country) FROM Customers");
        DropDownList ddlCountries = (e.Row.FindControl("ddlCountries") as DropDownList);
        ddlCountries.DataSource = this.ExecuteQuery(cmd, "SELECT");
        ddlCountries.DataTextField = "Country";
        ddlCountries.DataValueField = "Country";
        ddlCountries.DataBind();
        string country = (e.Row.FindControl("lblCountry") as Label).Text;
        ddlCountries.Items.FindByValue(country).Selected = true;
    }
}
protected void OnCheckedChanged(object sender, EventArgs e)
{
    bool isUpdateVisible = false;
    CheckBox chk = (sender as CheckBox);
    if (chk.ID == "chkAll")
    {
        foreach (GridViewRow row in gvCustomers.Rows)
        {
            if (row.RowType == DataControlRowType.DataRow)
            {
                row.Cells[0].Controls.OfType<CheckBox>().FirstOrDefault().Checked = chk.Checked;                    
            }
        }
    }
    CheckBox chkAll = (gvCustomers.HeaderRow.FindControl("chkAll") as CheckBox);
    chkAll.Checked = true;
    foreach (GridViewRow row in gvCustomers.Rows)
    {
        if (row.RowType == DataControlRowType.DataRow)
        {
            bool isChecked = row.Cells[0].Controls.OfType<CheckBox>().FirstOrDefault().Checked;
            for (int i = 1; i < row.Cells.Count; i++)
            {
                row.Cells[i].Controls.OfType<Label>().FirstOrDefault().Visible = !isChecked;
                if (row.Cells[i].Controls.OfType<TextBox>().ToList().Count > 0)
                {
                    row.Cells[i].Controls.OfType<TextBox>().FirstOrDefault().Visible = isChecked;
                }
                if (row.Cells[i].Controls.OfType<DropDownList>().ToList().Count > 0)
                {
                    row.Cells[i].Controls.OfType<DropDownList>().FirstOrDefault().Visible = isChecked;
                }
                if (isChecked && !isUpdateVisible)
                {
                    isUpdateVisible = true;
                }
                if (!isChecked)
                {
                    chkAll.Checked = false;
                }
            }
        }
    }
    btnUpdate.Visible = isUpdateVisible;
}

 Screenshot