Firing selected index changed event

Question

0.00/5 (No votes)

See more:

Hi,

I am Not able to fire selected index changed event.
I am retreiving previous combo box selected index
(string selectedstore_name = cmbRestaurant.Items[cmbRestaurant.SelectedIndex].ToString();)
but don't know how
i can use the same. Can someone guide me further with the same.

C#

private void LoadUsers()
{
 //string connectionString = null;
SqlConnection connection;
SqlDataAdapter adapter;
SqlCommand cmd = new SqlCommand();
DataSet D = new DataSet();

connection = new SqlConnection(connectionString);

connection.Open();
cmd.Connection = connection;

//Load user list
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "dbo.GetStore";
adapter = new SqlDataAdapter(cmd);
adapter.Fill(D);
cmbRestaurant.DataSource=D.Tables[0].DefaultView;
cmbRestaurant.DisplayMember = "store_name";
cmbRestaurant.ValueMember= "store_id";
cmd.Parameters.Clear();

connection.Close();
connection.Dispose();

}     

       private void cmbRestaurant_SelectedIndexChanged(object sender, EventArgs e)
       {

          string selectedstore_name = cmbRestaurant.Items[cmbRestaurant.SelectedIndex].ToString();

           SqlConnection connection = new SqlConnection(connectionString);
           SqlCommand cmd = new SqlCommand();
           cmd.CommandType = CommandType.Text;
           cmd.CommandText = "dbo.om_service_window, dbo.om_sw_location_map, dbo.om_Equipment";
           connection.Open();
          
           SqlDataAdapter adapter = new SqlDataAdapter(cmd);
          
           string Q2 = "select sw.sw_name from dbo.om_service_window sw join dbo.om_sw_location_map s on sw.sw_id=s.sw_id join dbo.om_Equipment e on s.point_location=e.point_location";
           adapter.SelectCommand = new SqlCommand(Q2, connection);
           adapter.SelectCommand.ExecuteNonQuery();
           DataSet DS2 = new DataSet();
           adapter.Fill(DS2, "D");
           DataTable DSTbl2 = DS2.Tables["D"];
           cmbServiceWindow.DataSource = DS2.Tables[0].DefaultView;
           cmbServiceWindow.DisplayMember = "sw_name";
           cmbServiceWindow.ValueMember = "sw_name";
           connection.Close();
           connection.Dispose();
           cmd.Parameters.Clear();
       }

       private void cmbServiceWindow_SelectedIndexChanged(object sender, EventArgs e)
       {
          string selectedservice_window = cmbServiceWindow.Items[cmbServiceWindow.SelectedIndex].ToString();
           // string ServiceWindow_name = cmbServiceWindow.Items[cmbServiceWindow.SelectedIndex].ToString();
           SqlConnection connection = new SqlConnection(connectionString);
           SqlCommand cmd = new SqlCommand();
           cmd.CommandType = CommandType.Text;
           cmd.CommandText = "dbo.om_Equipment";
           connection.Open();
           //cmd = new SqlCommand("select f.p_equip_id from dbo.om_equip_functionblock f join dbo.om_sw_location_map s on f.point_location=s.point_location join dbo.om_service_window sw on s.sw_id=sw.sw_id", connection);
           SqlDataAdapter adapter = new SqlDataAdapter(cmd);
           //DataSet ds = new DataSet();
           //adapter.Fill(ds);
           //cmbEquipments.DataSource = ds.Tables[0].DefaultView;
           //cmbEquipments.DisplayMember = "p_equip_id";
           //cmbServiceWindow.ValueMember = "selectedservice_window";
           //connection.Close();
           //connection.Dispose();
           //cmd.Parameters.Clear();
           string Q1 = "select distinct a.equip_desc from om_Equipment a right outer join om_Equipment b on a.equip_id=b.p_equip_id";
           adapter.SelectCommand = new SqlCommand(Q1, connection);
           adapter.SelectCommand.ExecuteNonQuery();
           DataSet DS1 = new DataSet();
           adapter.Fill(DS1, "D");
           DataTable DSTbl1 = DS1.Tables["D"];
           cmbEquipments.DataSource = DS1.Tables[0].DefaultView;
           cmbEquipments.DisplayMember = "equip_desc";
           cmbEquipments.ValueMember = "equip_desc";
           connection.Close();
           connection.Dispose();
           cmd.Parameters.Clear();
       }

       private void cmbEquipments_SelectedIndexChanged(object sender, EventArgs e)
       {
          string selectedEquipments = cmbEquipments.Items[cmbEquipments.SelectedIndex].ToString();
           // string ServiceWindow_name = cmbServiceWindow.Items[cmbServiceWindow.SelectedIndex].ToString();
           SqlConnection connection = new SqlConnection(connectionString);
           SqlCommand cmd = new SqlCommand();
           cmd.CommandType = CommandType.Text;
           cmd.CommandText = "dbo.om_Equipment";
           connection.Open();
          // cmd = new SqlCommand("select equip_id from dbo.om_equip_functionblock", connection);
           SqlDataAdapter adapter = new SqlDataAdapter(cmd);
           //DataSet ds = new DataSet();
           //adapter.Fill(ds);
           //cmbSubSystems.DataSource = ds.Tables[0].DefaultView;
           //cmbSubSystems.DisplayMember = "equip_id";
           //cmbSubSystems.ValueMember = "equip_id";
           //connection.Close();
           //connection.Dispose();
           //cmd.Parameters.Clear();
           string Q3 = "select distinct b.equip_id from om_Equipment a right outer join om_Equipment b on a.equip_id=b.p_equip_id";
           adapter.SelectCommand = new SqlCommand (Q3, connection);
           adapter.SelectCommand.ExecuteNonQuery();
           DataSet DS3 = new DataSet();
           adapter.Fill(DS3, "D");
           DataTable DSTbl1 = DS3.Tables["D"];
           cmbSubSystems.DataSource = DS3.Tables[0].DefaultView;
           cmbSubSystems.DisplayMember = "equip_id";
           cmbSubSystems.ValueMember = "equip_id";
           connection.Close();
           connection.Dispose();
           cmd.Parameters.Clear();
       }      

        }
    }

Posted 10-Jun-12 22:52pm

Kiran S.V

Updated 10-Jun-12 23:43pm

Sandeep Mewara

v2

Add a Solution

Comments

Sandeep Mewara 11-Jun-12 5:44am

Please correct your tags for the question. Winforms I guess.

Kiran S.V 11-Jun-12 6:53am

Yeah. I am retreiving the previous combobox values but don't know how to assign it for next combobox

string selectedstore_name = cmbRestaurant.Items[cmbRestaurant.SelectedIndex].ToString();
don't know where i can assign it?

RDBurmon 13-Jun-12 9:33am

Thanks Everyone who replied to this thread , So Kiran, I think you have got enough responses and you should be able to mark it as your answer and close the thread. Please do so.

4 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sebastian T Xavier · Answer 1 · 2012-06-11T20:44:00

Hi,

You can remove all the code from xxx_SelectedIndexChanged events and make it different methods and call these methods on these xxx_SelectedIndexChanged event . Then you can get the selected value of combo using folowing code....

C#

int selectedstore = cmbRestaurant.SelectedValue;

You can input this selected value to the next method and fetch related records only, (write the methods with appropriate parameters) and fill the next combo. This way you may be able to solve your problem.

regards
Sebastian

Sebastian T Xavier · Answer 2 · 2012-06-10T23:52:00

Solution 1

please check that your control & the event(cmbRestaurant_SelectedIndexChanged) is perfectly sync. I suspect that event is orphan, so it is not getting invoked.

Regards
Sebastian

Posted 10-Jun-12 23:52pm

Sebastian T Xavier

Comments

Kiran S.V 11-Jun-12 6:51am

No control & the event(cmbRestaurant_SelectedIndexChanged) are perfectly sync but on cmbRestaurant_SelectedIndexChanged i want 'cmbServiceWindow' combobox should be filled with only 'sw_name' but here all the comboboxes are populated when i select the index of (cmbRestaurant_SelectedIndexChanged) event.

Kiran S.V · Answer 3 · 2012-06-12T04:22:00

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Configuration;
using System.Data.SqlClient;
using Microsoft.CSharp;
using Excel = Microsoft.Office.Interop.Excel;

namespace ImportDataToExcelSP
{
public partial class Form1 : Form
{
private static readonly string connectionStringName = ConfigurationManager.AppSettings.Get("ConnectionString");
private static readonly string connectionString = connectionStringName;
public Form1()
{
InitializeComponent();

//cmbRestaurant.SelectedIndex = 0;
Restaurant();

}
public DataSet Restaurant()
{
SqlConnection connection;
SqlDataAdapter adapter;
SqlCommand cmd = new SqlCommand();
DataSet D = new DataSet();

connection = new SqlConnection(connectionString);

connection.Open();
cmd.Connection = connection;

//Load user list
cmd.CommandType = CommandType.Text;
cmd.CommandText = "dbo.om_Equipment";
adapter = new SqlDataAdapter(cmd);
string Q = "select point_location from dbo.om_Equipment";
adapter.SelectCommand = new SqlCommand(Q, connection);
adapter.SelectCommand.ExecuteNonQuery();
DataSet DS5 = new DataSet();
adapter.Fill(DS5, "DS5");
DataTable DSTbl5 = DS5.Tables["DS5"];
cmbRestaurant.DataSource = DS5.Tables[0].DefaultView;
cmbRestaurant.DisplayMember = "point_location";
cmbRestaurant.ValueMember = "point_location";
connection.Close();
connection.Dispose();
cmd.Parameters.Clear();
return D;

}

private void button1_Click(object sender, EventArgs e)
{

}

private void cmbRestaurant_SelectedIndexChanged(object sender, EventArgs e)
{
// string selectedStoreName = cmbRestaurant.SelectedIndex.ToString();
ServiceWindow();
}

public DataSet ServiceWindow()
{

String selectedStoreName = ((DataRowView)cmbRestaurant.SelectedItem).Row["point_location"].ToString();

SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "dbo.om_service_window, dbo.om_sw_location_map, dbo.om_Equipment";
connection.Open();

SqlDataAdapter adapter = new SqlDataAdapter(cmd);
//DataSet ds = new DataSet();
//adapter.Fill(ds);
//cmbServiceWindow.DataSource = ds.Tables[0].DefaultView;
//cmbServiceWindow.DisplayMember = "sw_name";
//cmbServiceWindow.ValueMember = "selectedstore_name";
////connection.Close();
//connection.Dispose();
//cmd.Parameters.Clear();
string Q2 = "select distinct sw.sw_name from dbo.om_service_window sw join dbo.om_sw_location_map s on sw.sw_id=s.sw_id join dbo.om_Equipment e on s.point_location=e.point_location where s.point_location='"+selectedStoreName.ToString() +"'";
adapter.SelectCommand = new SqlCommand(Q2, connection);
adapter.SelectCommand.ExecuteNonQuery();
DataSet DS2 = new DataSet();
adapter.Fill(DS2, "DS2");
DataTable DSTbl2 = DS2.Tables["DS2"];
cmbServiceWindow.DataSource = DS2.Tables[0].DefaultView;
cmbServiceWindow.DisplayMember = "sw_name";
cmbServiceWindow.ValueMember = "sw_name";
connection.Close();
connection.Dispose();
cmd.Parameters.Clear();
return DS2;
}

private void cmbServiceWindow_SelectedIndexChanged(object sender, EventArgs e)
{
Equipments();
}

public DataSet Equipments()
{
String ServiceWindow = ((DataRowView)cmbServiceWindow.SelectedItem).Row["sw_name"].ToString();
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "dbo.om_Equipment";
connection.Open();
//cmd = new SqlCommand("select f.p_equip_id from dbo.om_equip_functionblock f join dbo.om_sw_location_map s on f.point_location=s.point_location join dbo.om_service_window sw on s.sw_id=sw.sw_id", connection);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
//DataSet ds = new DataSet();
//adapter.Fill(ds);
//cmbEquipments.DataSource = ds.Tables[0].DefaultView;
//cmbEquipments.DisplayMember = "p_equip_id";
//cmbServiceWindow.ValueMember = "selectedservice_window";
//connection.Close();
//connection.Dispose();
//cmd.Parameters.Clear();
string Q1 = "select equip_id from dbo.om_Equipment where p_equip_id is null and point_location = 'IR_Schmale' ";
adapter.SelectCommand = new SqlCommand(Q1, connection);
adapter.SelectCommand.ExecuteNonQuery();
DataSet DS1 = new DataSet();
adapter.Fill(DS1, "DS1");
DataTable DSTbl1 = DS1.Tables["DS1"];
cmbEquipments.DataSource = DS1.Tables[0].DefaultView;
cmbEquipments.DisplayMember = "equip_id";
cmbEquipments.ValueMember = "equip_id";
connection.Close();
connection.Dispose();
cmd.Parameters.Clear();
return DS1;
}

private void cmbEquipments_SelectedIndexChanged(object sender, EventArgs e)
{
SubSystems();
}
public DataSet SubSystems()
{
String Equipments = ((DataRowView)cmbEquipments.SelectedItem).Row["equip_id"].ToString();
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "dbo.om_Equipment";
connection.Open();
// cmd = new SqlCommand("select equip_id from dbo.om_equip_functionblock", connection);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
//DataSet ds = new DataSet();
//adapter.Fill(ds);
//cmbSubSystems.DataSource = ds.Tables[0].DefaultView;
//cmbSubSystems.DisplayMember = "equip_id";
//cmbSubSystems.ValueMember = "equip_id";
//connection.Close();
//connection.Dispose();
//cmd.Parameters.Clear();
string Q3 = "select equip_id from dbo.om_Equipment where p_equip_id='PF' and point_location='IR_Schmale'";
adapter.SelectCommand = new SqlCommand(Q3, connection);
adapter.SelectCommand.ExecuteNonQuery();
DataSet DS3 = new DataSet();
adapter.Fill(DS3, "DS3");
DataTable DSTbl3 = DS3.Tables["DS3"];
cmbSubSystems.DataSource = DS3.Tables[0].DefaultView;
cmbSubSystems.DisplayMember = "equip_id";
cmbSubSystems.ValueMember = "equip_id";
connection.Close();
connection.Dispose();
cmd.Parameters.Clear();
return DS3;
}

private void cmbSubSystems_SelectedIndexChanged(object sender, EventArgs e)
{
Meter();
}

public DataSet Meter()
{
String SubSystems = ((DataRowView)cmbSubSystems.SelectedItem).Row["equip_id"].ToString();
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "dbo.r_equp_meter_map";
connection.Open();
// cmd = new SqlCommand("select equip_id from dbo.om_equip_functionblock", connection);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
//DataSet ds = new DataSet();
//adapter.Fill(ds);
//cmbSubSystems.DataSource = ds.Tables[0].DefaultView;
//cmbSubSystems.DisplayMember = "equip_id";
//cmbSubSystems.ValueMember = "equip_id";
//connection.Close();
//connection.Dispose();
//cmd.Parameters.Clear();
string Q4 = "select distinct source_type_id from dbo.r_equp_meter_map";
adapter.SelectCommand = new SqlCommand(Q4, connection);
adapter.SelectCommand.ExecuteNonQuery();
DataSet DS4 = new DataSet();
adapter.Fill(DS4, "DS4");
DataTable DSTbl4 = DS4.Tables["DS4"];
cmbMeter.DataSource = DS4.Tables[0].DefaultView;
cmbMeter.DisplayMember = "source_type_id";
cmbMeter.ValueMember = "source_type_id";
connection.Close();
connection.Dispose();
cmd.Parameters.Clear();
return DS4;
}

}
}

But all comboboxes are loading at a time.

SQL

(restaurant,service window,Equipments and subsystems) but i want to load them one by one.

On restaurant selected index change service window should be loaded like that.

Kiran S.V · Answer 4 · 2012-06-11T20:17:00

Solution 2

SQL

All the four Comboboxes are loading at a time (restaurant,service window,Equipments and subsystems) but i want to load them one by one.

On restaurant selected index change service window should be loaded like that.

Can anyone guide me how to get it?

Posted 11-Jun-12 20:17pm

Kiran S.V

Comments

Sebastian T Xavier 12-Jun-12 2:31am

This is Not an answer. please remove it and use the improve question link to update your question.

Kiran S.V 12-Jun-12 3:41am

Hi,

Thanks for your suggestion but when i tried to call the method and tried to pass
selectedstore into the other method i am getting error as
object reference not set to instance of object.

Sebastian T Xavier 12-Jun-12 6:10am

it seems that selectedstore is null. just check the selected value and the value in the variable.
Otherwise you post your new code & let me cross check it.

Firing selected index changed event

4 solutions

Solution 3

Solution 1

Solution 4

Solution 2

Add your solution here

Preview 0