Filter GridView records with Date selected from DropDownList in ASP.Net

Please Refer the below Example.

 HTML

  <form id="form1" runat="server">
    <div>
        <asp:DropDownList ID="ddlDOB" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlDOB_SelectedIndexChanged">
        </asp:DropDownList>
        <br />
        <asp:GridView ID="GvPersonalDetails" runat="server" AutoGenerateColumns="false">
            <Columns>
                <asp:BoundField DataField="Id" HeaderText="Id"></asp:BoundField>
                <asp:BoundField DataField="Name" HeaderText="Name"></asp:BoundField>
                <asp:BoundField DataField="LastName" HeaderText="LastName"></asp:BoundField>
            </Columns>
        </asp:GridView>
    </div>
    </form>

--Creates two procedure one for populate dropdown and other is for populate grid

CREATE Procedure PopulateBirthdate
AS
BEGIN
	select Distinct  CONVERT(VARCHAR(10),DOB,103) DOB
	From Personaldetails
END


CREATE Procedure PopulateDetailsByDOB
@DOB as Varchar(20)
AS
BEGIN
	select Id,Name,LastName
	From Personaldetails
	Where CONVERT(VARCHAR(10),DOB,103)=@DOB
END

/* Coding for Popuate Dropdown and populate grid on selection of date value from dropdownlist */

 protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            this.PopulateDOB();
        }
    }

    private void PopulateGrid()
    {
        string strConnString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(strConnString))
        {
            using (SqlCommand cmd = new SqlCommand("PopulateDetailsByDOB"))
            {
                using (SqlDataAdapter sda = new SqlDataAdapter())
                {
                    cmd.CommandType = CommandType.StoredProcedure;
                    cmd.Parameters.AddWithValue("@DOB", ddlDOB.SelectedValue.ToString());
                    cmd.Connection = con;
                    sda.SelectCommand = cmd;
                    using (DataTable dt = new DataTable())
                    {
                        sda.Fill(dt);
                        GvPersonalDetails.DataSource = dt;
                        GvPersonalDetails.DataBind();
                    }
                }
            }
        }
    }

    private void PopulateDOB()
    {
        string strConnString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(strConnString))
        {
            using (SqlCommand cmd = new SqlCommand("PopulateBirthdate"))
            {
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Connection = con;
                con.Open();
                SqlDataReader rdr;
                rdr = cmd.ExecuteReader();
                while (rdr.Read())
                {
                    ddlDOB.Items.Add(rdr[0].ToString());
                }
                con.Close();
            }
        }
    }
    protected void ddlDOB_SelectedIndexChanged(object sender, EventArgs e)
    {
        this.PopulateGrid();
    }