Search record with only with Date

 protected void Button2_Click(object sender, EventArgs e)
    {
        SqlCommand cmd = new SqlCommand("SELECT * FROM Transactions WHERE report_type = @report_type AND " + "[R_date] >= @date_t_s and [R_date] < @date_t_e");

        cmd.Connection = con;
        cmd.Parameters.Add("@report_type", SqlDbType.NVarChar).Value = DropDownList1.SelectedValue;
        cmd.Parameters.Add("@date_t_s", SqlDbType.DateTime).Value = DateTime.Parse(TextBox1.Text);
        cmd.Parameters.Add("@date_t_e", SqlDbType.DateTime).Value = DateTime.Parse(TextBox1.Text).AddDays(1);
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        da.Fill(ds);
        GridView1.DataSource = ds;
        GridView1.DataBind();
}