Filter Records GridView by Selecting Column Name from DropDownList and Search Term from TextBox in ASP.Net

Hi parthiban,

Try the following...

 <asp:DropDownList ID="ddlSearchItems" runat="server">
        </asp:DropDownList>
        <asp:TextBox ID="txtSearch" runat="server"></asp:TextBox>
        <br />
        <br />
        <asp:Button ID="btnSearch" runat="server" Text="Search" OnClick="Search" />
        <asp:GridView ID="gvEmployees" runat="server" AutoGenerateColumns="false">
            <Columns>
                <asp:BoundField DataField="EmployeeId" HeaderText="Employee Id" />
                <asp:BoundField DataField="FirstName" HeaderText="Name" />
                <asp:BoundField DataField="City" HeaderText="City" />
                <asp:BoundField DataField="Country" HeaderText="Country" />
            </Columns>
        </asp:GridView>

Code

protected void Page_Load(object sender, EventArgs e)
        {
            if (!this.IsPostBack)
            {
                this.BindSearchTerm();
            }
        }
        string query = "SELECT EmployeeId,FirstName,City,Country FROM Employees";
        protected void Search(object sender, EventArgs e)
        {
            string constr = @"Data Source=192.168.0.1\SQL2005;Initial Catalog=Northwind;User=sa;Password=pass@123";
            query += string.Format(" WHERE {0} = '{1}'", this.ddlSearchItems.SelectedItem.Text.Trim(), this.txtSearch.Text.Trim());
            this.gvEmployees.DataSource = this.GetData(constr, query);
            this.gvEmployees.DataBind();
        }

        private void BindSearchTerm()
        {
            string constr = @"Data Source=192.168.0.1\SQL2005;Initial Catalog=Sample;User=sa;Password=pass@123";
            this.ddlSearchItems.DataSource = this.GetData(constr, "SELECT Name FROM SearchTerm");
            this.ddlSearchItems.DataTextField = "Name";
            this.ddlSearchItems.DataValueField = "Name";
            this.ddlSearchItems.DataBind();
        }

        private DataTable GetData(string constr, string query)
        {
            DataTable dt = new DataTable();
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand(query))
                {
                    using (SqlDataAdapter sda = new SqlDataAdapter())
                    {
                        cmd.CommandType = CommandType.Text;
                        cmd.Connection = con;
                        sda.SelectCommand = cmd;
                        sda.Fill(dt);
                    }
                }
                return dt;
            }
        }

Namespaces

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