the sql query is not working.im using service based database

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Configuration;

using System.Data;

using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page

{

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["bs"].ConnectionString);

SqlCommand cmd;

SqlDataAdapter da;

DataSet ds;

string sql_query;

protected void Page_Load(object sender, EventArgs e)

{

}

protected void btn_Add_Click(object sender, EventArgs e)

{

try

{

sql_query = "Insert into BookRecord(bookid, bookname, bookpubname, bookpubyear, bookprice, bookquantity, recorddate) values('" + txt_bookid.Text.Trim() + "','" + txt_bookname.Text.Trim() + "','" + txt_bookpubname.Text.Trim() + "','" + txt_bookpubyear.Text.Trim() + "','" + txt_bookprice.Text.Trim() + "','" + txt_bookqty.Text.Trim() + "','" + DateTime.Today.Date.ToShortDateString() + "')";

cmd = new SqlCommand(sql_query, con);

con.Open();

cmd.ExecuteNonQuery();

con.Close();

lblresult.Text = "Record Inserted Successfully...";

}

catch

{

con.Close();

}

}

protected void btn_Add_Reset_Click(object sender, EventArgs e)

{

ResetTextbox();

}

private void ResetTextbox()

{

txt_bookid.Text = "";

txt_bookname.Text = "";

txt_bookpubname.Text = "";

txt_bookpubyear.Text = "";

txt_bookprice.Text = "";

txt_bookqty.Text = "";

}

private void ResetEditTextbox()

{

txt_edit_bookid.Text = "";

txt_edit_bookid.Style.Add("width", "235px");

txt_edit_bookid.Style.Add("background", "#ffffff");

txt_edit_bookid.ReadOnly = false;

btn_check.Visible = true;

txt_edit_bookname.Text = "";

txt_edit_bookpubname.Text = "";

txt_edit_bookpubdate.Text = "";

txt_edit_bookprice.Text = "";

txt_edit_bookqty.Text = "";

}

private void ResetDeleteTextbox()

{

txt_delete_bookid.Text = "";

}

private void DisableReadOnly_EditTextBoxColor()

{

txt_edit_bookname.ReadOnly = true;

txt_edit_bookname.Style.Add("background", "#dddddd");

txt_edit_bookpubname.ReadOnly = true;

txt_edit_bookpubname.Style.Add("background", "#dddddd");

txt_edit_bookpubdate.ReadOnly = true;

txt_edit_bookpubdate.Style.Add("background", "#dddddd");

txt_edit_bookprice.ReadOnly = true;

txt_edit_bookprice.Style.Add("background", "#dddddd");

txt_edit_bookqty.ReadOnly = true;

txt_edit_bookqty.Style.Add("background", "#dddddd");

}

protected void btn_Add_Cancel_Click(object sender, EventArgs e)

{

ResetTextbox();

}

// Check Book Detail through BookID

protected void btn_check_Click(object sender, EventArgs e)

{

try

{

sql_query = "Select * from BookRecord Where bookid='" + txt_edit_bookid.Text.Trim() + "'";

da = new SqlDataAdapter(sql_query, con);

ds = new DataSet();

da.Fill(ds);

if (ds.Tables[0].Rows.Count > 0)

{

txt_edit_bookid.Text = ds.Tables[0].Rows[0]["bookid"].ToString();

txt_edit_bookname.Text = ds.Tables[0].Rows[0]["bookname"].ToString();

txt_edit_bookpubname.Text = ds.Tables[0].Rows[0]["bookpubname"].ToString();

txt_edit_bookpubdate.Text = ds.Tables[0].Rows[0]["bookpubyear"].ToString();

txt_edit_bookprice.Text = ds.Tables[0].Rows[0]["bookprice"].ToString();

txt_edit_bookqty.Text = ds.Tables[0].Rows[0]["bookquantity"].ToString();

btn_check.Visible = false;

EnableReadOnly_TextBoxColor();

div_add.Style.Add("display", "none");

table_Add.Style.Add("display", "none");

div_edit.Style.Add("display", "block");

table_Edit.Style.Add("display", "block");

div_delete.Style.Add("display", "none");

table_Delete.Style.Add("display", "none");

txt_edit_bookid.Style.Add("width", "300px");

txt_edit_bookid.Style.Add("background", "#dddddd");

txt_edit_bookid.ReadOnly = true;

}

}

catch

{

con.Close();

}

}

private void EnableReadOnly_TextBoxColor()

{

txt_edit_bookid.ReadOnly = false;

txt_edit_bookid.Style.Add("background","#ffffff");

txt_edit_bookname.ReadOnly = false;

txt_edit_bookname.Style.Add("background","#ffffff");

txt_edit_bookpubname.ReadOnly = false;

txt_edit_bookpubname.Style.Add("background","#ffffff");

txt_edit_bookpubdate.ReadOnly = false;

txt_edit_bookpubdate.Style.Add("background","#ffffff");

txt_edit_bookprice.ReadOnly = false;

txt_edit_bookprice.Style.Add("background","#ffffff");

txt_edit_bookqty.ReadOnly = false;

txt_edit_bookqty.Style.Add("background","#ffffff");

}

protected void btn_Update_Click(object sender, EventArgs e)

{

try

{

sql_query = "Update BookRecord set bookname='" + txt_edit_bookname.Text.Trim() + "', bookpubname='" + txt_edit_bookpubname.Text.Trim() + "', bookpubyear='" + txt_edit_bookpubdate.Text.Trim() + "', bookprice='" + txt_edit_bookprice.Text.Trim() + "', bookquantity='" + txt_edit_bookqty.Text.Trim() + "' where bookid='" + txt_edit_bookid.Text.Trim() + "'";

cmd = new SqlCommand(sql_query, con);

con.Open();

cmd.ExecuteNonQuery();

con.Close();

lblresult.Text = "Record Updated Successfully...";

}

catch

{

con.Close();

}

}

protected void btn_Update_Reset_Click(object sender, EventArgs e)

{

ResetEditTextbox();

DisableReadOnly_EditTextBoxColor();

}

protected void btn_Update_Cancel_Click(object sender, EventArgs e)

{

ResetEditTextbox();

DisableReadOnly_EditTextBoxColor();

}

protected void btn_Delete_Click(object sender, EventArgs e)

{

try

{

sql_query = "Delete BookRecord where bookid='" + txt_delete_bookid.Text.Trim() + "'";

cmd = new SqlCommand(sql_query, con);

con.Open();

cmd.ExecuteNonQuery();

con.Close();

div_add.Style.Add("display", "none");

table_Add.Style.Add("display", "none");

div_edit.Style.Add("display", "none");

table_Edit.Style.Add("display", "none");

div_delete.Style.Add("display", "block");

table_Delete.Style.Add("display", "block");

lblresult.Text = "Record Deleted Successfully...";

}

catch

{

con.Close();

}

}

protected void btn_Delete_Reset_Click(object sender, EventArgs e)

{

ResetDeleteTextbox();

}

protected void btn_Delete_Cancel_Click(object sender, EventArgs e)

{

ResetDeleteTextbox();

}

}