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Fill combobox with multiple datasets from the same database column at the same time

I have a combobox that is filled from a database conditionally by checking off one of 10 checkboxes. Each of the 10 checkboxes contains the code below, which selects a portion of column based on a value in column2.
private void Check1_CheckedChanged(object sender, EventArgs e)
{
if (Check1.CheckState == CheckState.Checked)
{
// SQL Server connection
SqlConnection conn = new SqlConnection(#"Server = Server; Database = DB; Integrated Security = True");
DataSet ds = new DataSet();
try
{
conn.Open();
SqlCommand cmd = new SqlCommand("SELECT [Column1] FROM [DB].[dbo].[Table1] WHERE [Column2] = 50", conn);
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
da.Fill(ds);
combo1.DisplayMember = "Column1";
combo1.ValueMember = "ID";
combo1.DataSource = ds.Tables[0];
}
catch (Exception ex)
{
//Exception Message
}
finally
{
conn.Close();
conn.Dispose();
}
}
if (Check1.CheckState == CheckState.Unchecked)
{
combo1.DataSource = null;
}
Therefore, it is rather trivial to fill the combobox with each separate condition. What I want to do that I'm not sure of the approach, however, is that when more than one checkbox is checked, the combobox will display the data from every checked checkbox at once (all this data will be from the same column). Moreover, when a single checkbox is then unchecked, I only want it to remove its own dataset from the combobox and not everything.
Is this possible?

I think it's possible if you have 1 dataset and then you dynamically build up your SQL query. Set up a variable for the columns you want to return based on all the selected comboBoxes.
Use 1 method for all your after update event on the comboBoxes to make it easier and more maintainable.
In terms of mapping the dynamics columns to the dropdowns, I don't work with Winform so I'm not sure but hope this can help a bit.

You can use the for loop to iterate the values you have retrieved and append the combo box value. Example:
comboBox.Items.Clear(); // <-- Declare this at initialization of the page or whatever scenario you have
private void Check1_CheckedChanged(object sender, EventArgs e)
{
if (Check1.CheckState == CheckState.Checked)
{
// SQL Server connection
SqlConnection conn = new SqlConnection(#"Server = Server; Database = DB; Integrated Security = True");
DataSet ds = new DataSet();
try
{
conn.Open();
SqlCommand cmd = new SqlCommand("SELECT [Column1] FROM [DB].[dbo].[Table1] WHERE [Column2] = 50", conn);
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
da.Fill(ds);
// Using loop to iterate the values and append the combo box
for(int i=0;i<da.Rows.Count;i++)
{
combo1.Items.Add(da[i]["Column1"].ToString());
combo1.Items[combo1.Itemx.Count-1].Text=da[i]["Column1"].ToString();
combo1.Items[combo1.Itemx.Count-1].Value=da[i]["Column1"].ToString();
}
}
catch (Exception ex)
{
//Exception Message
}
finally
{
conn.Close();
conn.Dispose();
}
}
if (Check1.CheckState == CheckState.Unchecked)
{
combo1.DataSource = null;
}
This is just an example, hope you can get the idea

How to get data from SQL and write it in textbox?

I need a help.
I searched and I tried a lot but I am too bad to make it work on my project by myself.
This is code for button-Seek. I want to make Seek-button to fill textbox by respective data.
private void SeekClick(object sender, EventArgs e)
{
if (TBCusNumber.Text != "")
{
string Number = TBCusNumber.Text;
var Conn = new SqlConnection();
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["WindowsFormsApp1.Properties.Settings.DataBase"].ConnectionString;
var Cmd = new SqlCommand();
Cmd.Connection = Conn;
Cmd.CommandText = "SELECT * FROM CustomerList WHERE CustomerNumber = " + Number;
var DataAdapter = new SqlDataAdapter(Cmd);
DataSet DataSet = new DataSet();
DataAdapter.Fill(DataSet, "CustomerList");
CusView.DataSource = DataSet;
CusView.DataMember = "CustomerList";
}
}
And This is the data table.
This is what happens when I put 3 in the text box and press Seek-button.
So here, I want all text boxes to be filled by the data which I searched.

You will get only one row for the query right?
So give like that,
txtFirstName.Text = DataSet.Tables[0].Rows[0]["FirstName"].ToString();
txtLasttName.Text = DataSet.Tables[0].Rows[0]["LastName"].ToString();
Like this you need to assign the values to the respective text boxes.

There are three problem need to fix.
You forget to open the connection with DB,add Conn.Open(); before you excute sql command.
You need to add parameter to prevention SQL Injection
Please use using it will help you to use external resources to return the memory.
when the DataSet be filled you can get the data then fill in textbox
You can follow like this.
private void SeekClick(object sender, EventArgs e)
{
if (TBCusNumber.Text != "")
{
string Number = TBCusNumber.Text;
using (var Conn = new SqlConnection())
{
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["WindowsFormsApp1.Properties.Settings.DataBase"].ConnectionString;
using (var Cmd = new SqlCommand())
{
Cmd.Connection = Conn;
Cmd.CommandText = "SELECT * FROM CustomerList WHERE CustomerNumber = #Number";
Cmd.Parameters.AddWithValue("#Number", Number);
//You miss to add Conn.Open()
Conn.Open();
using (var DataAdapter = new SqlDataAdapter(Cmd))
{
DataSet DataSet = new DataSet();
DataAdapter.Fill(DataSet, "CustomerList");
CusView.DataSource = DataSet;
CusView.DataMember = "CustomerList";
//when the DataSet be filled you can get the data then fill in textbox
txt_firstName.Text = DataSet.Tables[0].Rows[0]["FirstName"].ToString();
}
}
}
}
}

Connection to SQL Server through ADO.NET - Empty Listbox

Trying to set up a connection to my local SQL Server Express instance so that I can display columns in a listbox. Th build runs fine and I can't see errors, but there is no data in the listbox. I have tested the query and that is fine. I am using NT Authentication to the database. Any ideas where I might have gone wrong?
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void customers_SelectedIndexChanged(object sender, EventArgs e)
{
string commstring = "Driver ={SQL Server}; Server = DESKTOP-5T4MHHR\\SQLEXPRESS; Database = AdventureWorks2014; Trusted_Connection = Yes;";
string connstring = "SELECT FirstName, LastName FROM Person.Person";
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
DataSet customerDataSet = new DataSet();
customerDataAdapater.Fill(customerDataSet, "Person.Person");
DataTable customerDataTable = new DataTable();
customerDataTable = customerDataSet.Tables[0];
foreach (DataRow dataRow in customerDataTable.Rows)
{
customers.Items.Add(dataRow["FirstName"] + " (" + dataRow["LastName"] + ")");
}
}
}

I tested your code in a sample project here and I realized you passed the parameters to SqlDataAdapter constructor in a wrong order.
After changing the follow line:
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
by
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(connstring, commstring);
the listbox was filled successfully.

Your connection string seems weird.....
Could you try using just this:
string commstring = "Server=DESKTOP-5T4MHHR\\SQLEXPRESS;Database=AdventureWorks2014;Trusted_Connection=Yes;";
Also: why are you first creating a DataSet, filling in a single set of data, and then extracting a DataTable from it?? This is unnecessarily complicated code - just use this instead:
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
// if you only ever need *one* set of data - just use a DataTable directly!
DataTable customerDataTable = new DataTable();
// Fill DataTable with the data from the query
customerDataAdapater.Fill(customerDataTable);
Update: I would really rewrite your code to something like this:
// create a separate class - call it whatever you like
public class DataProvider
{
// define a method to provide that data to you
public List<string> GetPeople()
{
// define connection string (I'd really load that from CONFIG, in real world)
string connstring = "Server=MSEDTOP;Database=AdventureWorks2014;Trusted_Connection=Yes;";
// define your query
string query = "SELECT FirstName, LastName FROM Person.Person";
// prepare a variable to hold the results
List<string> entries = new List<string>();
// put your SqlConnection and SqlCommand into "using" blocks
using (SqlConnection conn = new SqlConnection(connstring))
using (SqlCommand cmd = new SqlCommand(query, conn))
{
conn.Open();
// iterate over the results using a SqlDataReader
using (SqlDataReader rdr = cmd.ExecuteReader())
{
while (rdr.Read())
{
// get first and last name from current row of query
string firstName = rdr.GetFieldValue<string>(0);
string lastName = rdr.GetFieldValue<string>(1);
// add entry to result list
entries.Add(firstName + " " + lastName);
}
rdr.Close();
}
conn.Close();
}
// return the results
return entries;
}
}
And in your code-behind, you only need to do something like this:
protected override void OnLoad(.....)
{
if (!IsPostback)
{
List<string> people = new DataProvider().GetPeople();
customers.DataSource = people;
customers.DataBind();
}
}
but I still don't understand what you were trying to when the SelectedIndexChanged event happens.....

Listbox isn't populating with Data

I have set up a listbox called lboxsupplier, i have also created a data adapter which i then used to populate the supplier listbox. When i run the form the listbox is empty. I want the listbox to populate with supplier ID and company which i will then click on to populate another listbox with products.
Namespace Pennyburn_Greg
{
public partial class FormProcess : Form
{
SqlDataAdapter daSupplier;
DataSet dsPennyburnGreg = new DataSet();
SqlConnection conn;
SqlCommand cmdSupplierDetails;
SqlCommandBuilder cmdBSupplier;
DataRow drSupplier;
String connstr, sqlSupplier;
public FormProcess()
{
InitializeComponent();
}
private void FormProcess_Load(object sender, EventArgs e)
{
connstr = #"Data Source= arlene-pc; Initial Catalog= PennyburnGreg; Integrated Security=True";
//dataAdapter for supplier listbox
sqlSupplier = #"Select* from Supplier";
conn = new SqlConnection(connstr);
cmdSupplierDetails = new SqlCommand(sqlSupplier, conn);
daSupplier = new SqlDataAdapter(cmdSupplierDetails);
daSupplier.FillSchema(dsPennyburnGreg, SchemaType.Source, "Supplier");
}
private void filllboxsupplier(string str)
{
daSupplier.Fill(dsPennyburnGreg, "Supplier");
lboxsupplier.DataSource = dsPennyburnGreg.Tables["Supplier"];
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
}
}
}

First of all, why are you calling FillSchema, rather should be calling Fill method to get the data, like
daSupplier.Fill(dsPennyburnGreg, "Supplier");
Once you have the dataset filled, then in your FormProcess_Load() you can add the dataset as datasource to the listbox like
lboxsupplier.DataSource = dsPennyburnGreg.Tables["Supplier"]

First thing you need to do is loosely couple your UI and data a little bit. Try this code:
// Returns a DataTable of ALL suppliers
private DataTable GetSuppliers()
{
return GetSuppliers(0);
}
// Returns a DataTable of the given supplier
private DataTable GetSuppliers(int supplierId)
{
using (var connection = new SqlCommand())
{
connection.ConnectionString = #"Data Source= arlene-pc; Initial Catalog= PennyburnGreg; Integrated Security=True";
using (var command = new SqlCommand())
{
connection.Open();
command.CommandType = CommandType.Text;
command.Connection = connection;
if (supplierId == 0)
{
command.commandText = "SELECT * FROM Supplier";
}
else
{
command.commandText = "SELECT * FROM Supplier WHERE SupplierId=#id";
command.Parameters.AddWithValue("#id", supplierId);
}
using (var adapter = new SqlDataAdapter())
{
using (var ds = new DataSet())
{
adapter.SelectCommand = command;
adapter.Fill(ds);
if (ds.Tables.Count > 0)
return ds.Tables[0];
}
}
}
}
return null;
}
And now you can just do this:
lboxsupplier.DataSource = GetSuppliers(int.Parse(lboxsupplier.SelectedValue));
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
Or if you need all Suppliers, just do this:
lboxsupplier.DataSource = GetSuppliers();
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
This code will provide some separation. This is still not ideal, but beats what you had.

You're not doing anything with the listbox control in FormProcess_Load, so it will be empty when it first loads. I'm assuming you have lboxsupplier_Click bound to the Click event of lboxsupplier? If so, then you'll need to click on that listbox before it will populate the Dataset (which is a very odd user experience, but if that's truly what you need...). If lboxsupplier_Click isn't an event handler, then you're going to have to manually call it.
If it still isn't populating, then try running your query against the database directly, and make sure that it returns data and has columns named "Company" and "SupplierID"

How to get the data when I select a datagridview cell or column

I have 2 datagridview controls in a Windows Forms application.
I would like to get the info of a person when I select first datagridview cell or row to next datagridview:
try
{
ConnectionStringSettings consettings = ConfigurationManager.ConnectionStrings["attendancemanagement"];
string connectionString = consettings.ConnectionString;
SqlConnection con = new SqlConnection(connectionString);
con.Open();
adap3 = new SqlDataAdapter(#"SELECT Date,Attendance,Remarks FROM dailyattendance where employee_id='"+DailyGV.CurrentRow+"'", con);
ds3 = new DataSet();
adap3.Fill(ds3, "dailyattendance");
dataGridView1.DataSource = ds3.Tables[0];
}
Im trying the above code. But it's not working.

I'm not too sure what DailyGV.CurrentRow is but basically you can use the RowHeaderMouseClick...see MSDN documentation. To use it, hook an event handler to it when initializing the form components (you can use VS designer as well...
dataGridView1.RowHeaderMouseClick += dataGridView1_RowHeaderMouseClick;
void dataGridView1_RowHeaderMouseClick(
object sender, DataGridViewCellMouseEventArgs e)
{
}
this event handler will get fired everytime you select a row header in the DataGridView control which will pass information about the event through an instance of the DataGridViewCellMouseEventArgs class (see MSDN documentation). This argument has a RowIndex property that provides the index of the row clicked which you can use to retrieve the values of the cells in that row...including the person id (if provided)...for example...
void dataGridView1_RowHeaderMouseClick(
object sender, DataGridViewCellMouseEventArgs e)
{
string personId = dataGridView1.Rows[e.RowIndex].Cells["PersonId"].Value;
//TODO: implement your own query to retrieve data for that person id
}
notice that you need to provide a proper column name when access the cells collection indexer...Cells["columnName"]

I will not give any description about the solution because Leo and Arsalan Bhatti has already suggested the solution. I am just telling you how your code should looks like and how it should be written.
string connectionString = consettings.ConnectionString;
using (SqlConnection con = new SqlConnection(connectionString))
{
try
{
con.Open();
string empID = DailyGV.CurrentRow.Cells["employee_id"].Value.ToString();
SqlCommand Cmd = con.CreateCommand();
Cmd.CommandText = "SELECT Date,Attendance,Remarks FROM dailyattendance where employee_id=#employee_id";
Cmd.Parameters.Add("#employee_id", SqlDbType.Int).Value = Int32.Parse(empID);
adap3 = new SqlDataAdapter(Cmd);
DataTable dt = new DataTable();
adap3.Fill(dt);
dataGridView1.DataSource = dt;
con.Close();
}
catch
{}
}

try
{
cn.Open();
string query = "select employee_id,Employee_Name,Image_of_Employee from Employee_Details where employee_id='" + dataGridView1.SelectedCells[0].Value.ToString() + "'";
SqlCommand cmd = new SqlCommand(query, cn);
SqlDataReader sdr;
sdr = cmd.ExecuteReader();
if (sdr.Read())
{
string aa = (string)sdr["employee_id"];
string bb = (string)sdr["employee_name"];
txtEmployeeID.Text = aa.ToString();
txtnameofemployee.Text = bb.ToString();
byte[] img=(byte[])sdr["Image_of_employee"];
MemoryStream ms=new MemoryStream(img);
ms.Seek(0,SeekOrigin.Begin);
pictureBox1.Image=Image.FromStream(ms); cn.Close();
}
}
catch (Exception e1)
{
MessageBox.Show(e1.Message);
}

You are passing the current row's index as employee id in SELECT query. Pass employee id for the selected record. Then it will work fine.