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C# - Pull SQL data to textboxes/labels from changing combobox selected item

So I'm trying to create sort of an overview utility of sites, with different infos on each site.
I'd like to have a dropdown list / combobox, reading a sqldb and create items according to the db. Then I would like different textboxes to get populated with a value from a column.
Say my db table is called "AvSites" so far (just for the sake of it) i have "projectNr", "siteName", "siteClients" and "siteLicenses" columns I'd like each of these to populate some textbox / label somewhere.
I've tried the following, which kinda works, Ive had the code working most of the time, but the thing that defeats me is having the data change with the combobox item selected.
I hope you can help, and so here is my code so far (I have a login window, before this "main" program starts, just so you're not wondering)
And I'm quite new to C# so if there's something thats done inefficient thats the reason :) Im still learning.
namespace AvOverview{
public partial class frmMain : Form
{
public frmMain()
{
InitializeComponent();
}
private void Button1_Click(object sender, EventArgs e)
{
//btn_LogOut Click Event
this.Hide();
Form1 fl = new Form1();
fl.Show();
}
private void frmMain_FormClosing(object sender, FormClosingEventArgs e)
{
Application.Exit();
}
private void FrmMain_Load(object sender, EventArgs e)
{
string cs = #"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\Database1.mdf";
SqlConnection con = new SqlConnection(cs);
con.Open();
string strCmd = "select * from AvSites";
SqlCommand cmd = new SqlCommand(strCmd, con);
SqlDataAdapter da = new SqlDataAdapter(strCmd, con);
DataSet ds = new DataSet();
da.Fill(ds);
combo1.ValueMember = "id";
combo1.DisplayMember = "siteName";
combo1.DataSource = ds.Tables[0];
combo1.Enabled = true;
this.combo1.SelectedIndex = -1;
cmd.ExecuteNonQuery();
con.Close();
}
private void Combo1_SelectedIndexChanged(object sender, EventArgs e)
{
string cs = #"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\Database1.mdf";
string strCmd = "select id from AvSites";
SqlConnection con = new SqlConnection(cs);
SqlCommand cmd = new SqlCommand(strCmd, con);
con.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{//this last part is solely for testing if the text changed the way I wanted.
label1.Text = dr.GetValue(1).ToString();
label2.Text = dr.GetValue(2).ToString();
label3.Text = dr.GetValue(0).ToString();
label4.Text = dr.GetValue(3).ToString();

You don't need to call the database again. All the info are in the current selected item.
When you set the DataSource of your combo to a datatable like you do in the click event each element of the combo is a DataRowView and from this element you can get all the info extracted from the database from your initial query
private void Combo1_SelectedIndexChanged(object sender, EventArgs e)
{
DataRowView rv = Combo1.SelectedItem as DataRowView;
if(rv != null)
{
label1.Text = rv[1].ToString();
label2.Text = rv[2].ToString();
label3.Text = rv[0].ToString();
label4.Text = rv[3].ToString();
}
}
Side note: There are some improvements needed in your code.
First you should store the connection string in the config file and read it back with the ConfigurationManager class. Read about Configuration in NET
Second you shouldn't work with disposable objects like you do now. A disposable object should be disposed as soon as you have finished to use it. In particular the SqlConnection keeps valuable system resources both on your machine and on the server. You should start to use the using statement
string strCmd = "select * from AvSites";
using(SqlConnection con = new SqlConnection(.......))
using(SqlCommand cmd = new SqlCommand(strCmd, con)))
{
con.Open();
SqlDataAdapter da = new SqlDataAdapter(strCmd, con);
DataSet ds = new DataSet();
da.Fill(ds);
combo1.ValueMember = "id";
combo1.DisplayMember = "siteName";
combo1.DataSource = ds.Tables[0];
combo1.Enabled = true;
this.combo1.SelectedIndex = -1;
// ??? not needed ==> cmd.ExecuteNonQuery();
// not needed with using ==> con.Close();
}
// Here the connection is closed and disposed and resources are released

Update mysql database from datagridview selected row

i have a datagridview which loads mysql database table t_pi_clients on form load event,and i have another tab which contains textboxes of the respective columns of t_pi_client, which am able to get data from fullrowselect mode into those textboxes. now i want to update the database upon changes in the those textbox values. so far i've tried some process and gets my "entry saved" messageBox.show but nothing happens to database, so am hoping someone could help me out maybe am missing something thanks
public partial class frmMain : Form
{
MySqlConnection connection;
MySqlDataAdapter mySqlDataAdapter;
DataSet dt = new DataSet();
DataSet DS = new DataSet();
DataSet dg = new DataSet();
public frmMain()
{
InitializeComponent();
}
#region Main load
private void frmMain_Load(object sender, EventArgs e)
{
var connectionString = ConfigurationManager.ConnectionStrings["Pigen"].ConnectionString;
connection = new MySqlConnection(connectionString);
if (this.OpenConnection() == true)
{
mySqlDataAdapter = new MySqlDataAdapter("select * from t_pi_Clients", connection);
DataSet DS = new DataSet();
mySqlDataAdapter.Fill(DS);
kryptonDataGridView1.DataSource = DS.Tables[0];
kryptonDataGridView1.Columns[0].Visible = false;
mySqlDataAdapter = new MySqlDataAdapter("select * from t_pi_msg_charge_Rate", connection);
DataSet dt = new DataSet();
mySqlDataAdapter.Fill(dt);
kryptonDataGridView2.DataSource = dt.Tables[0];
mySqlDataAdapter = new MySqlDataAdapter("select * from t_pi_client_deposits", connection);
DataSet dg = new DataSet();
mySqlDataAdapter.Fill(dg);
kryptonDataGridView3.DataSource = dg.Tables[0];
}
}
//loads selected row data into textboxes
private void kryptonDataGridView1_DoubleClick(object sender, EventArgs e)
{
textboxClientCode.Text = kryptonDataGridView1.SelectedRows[0].Cells["ClientCode"].Value.ToString();
txtboxClientName.Text = kryptonDataGridView1.SelectedRows[0].Cells["ClientName"].Value.ToString();
txtboxPostalAddress.Text = kryptonDataGridView1.SelectedRows[0].Cells["PostalAdd"].Value.ToString();
txtboxTelephone.Text = kryptonDataGridView1.SelectedRows[0].Cells["Telephone"].Value.ToString();
txtboxFax.Text = kryptonDataGridView1.SelectedRows[0].Cells["Fax"].Value.ToString();
txtboxEmailAddress1.Text = kryptonDataGridView1.SelectedRows[0].Cells["EmailAdd1"].Value.ToString();
txtboxEmailAddress2.Text = kryptonDataGridView1.SelectedRows[0].Cells["EmailAdd2"].Value.ToString();
txtboxEmailAddress3.Text = kryptonDataGridView1.SelectedRows[0].Cells["EmailAdd3"].Value.ToString();
txtboxWebsite.Text = kryptonDataGridView1.SelectedRows[0].Cells["Website"].Value.ToString();
txtboxChargeRate.Text = kryptonDataGridView1.SelectedRows[0].Cells["ChargeRate"].Value.ToString();
txtboxTotalDepo.Text = kryptonDataGridView1.SelectedRows[0].Cells["TotalDeposit"].Value.ToString();
txtboxAccountBal.Text = kryptonDataGridView1.SelectedRows[0].Cells["AccountBal"].Value.ToString();
txtboxEntrydate.Text = kryptonDataGridView1.SelectedRows[0].Cells["EntryDate"].Value.ToString();
}
now i tried this method to update but doesn't update database
private void kryptonbtnUpdate_Click(object sender, EventArgs e)
{
var connectionString = ConfigurationManager.ConnectionStrings["Pigen"].ConnectionString;
using (MySqlConnection Conn = new MySqlConnection(connectionString))
if (Conn.State.ToString() != "Open")
{
}
else
{
connection.Open();
}
try
{
DataTable changes = ((DataTable)kryptonDataGridView1.DataSource).GetChanges();
if (changes != null)
{
MySqlCommandBuilder mcb = new MySqlCommandBuilder(mySqlDataAdapter);
mySqlDataAdapter.UpdateCommand = mcb.GetUpdateCommand();
mySqlDataAdapter.Update(changes);
((DataTable)kryptonDataGridView1.DataSource).AcceptChanges();
mySqlDataAdapter.Update(DS);
}
// adapter.Update(rowsToUpdate);
// mySqlDataAdapter.Update(DS);
MessageBox.Show("Entry Saved");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}

This is just a pseudocode of what you need to do
string cmdText = #"UPDATE t_pi_Clients
SET ClientName = #ClientName,
PostalAdd = #PostalAdd,
Telephone = #Telephone,
Fax = #Fax,
.... etc ....
WHERE ClientCode = #ClientCode";
using(MySqlConnection cn = new MySqlConnection(.....))
using(MySqlCommand cmd = new MySqlCommand(cmdText, cn))
{
cn.Open();
cmd.Parameters.AddWithValue("#ClientName", txtboxClientName.Text);
cmd.Parameters.AddWithValue("#PostalAdd", txtboxPostalAddress.Text);
....etc etc...
cmd.Parameters.AddWithValue("#ClientCode", textboxClientCode.Text);
int rowsUpdated = cmd.ExecuteNonQuery();
if(rowsUpdated > 0)
{
// extract the code that loads DataGridView1 from the Form_Load
// and create a reusable method that you could call from here
}
}
First you build an sql command text with the UPDATE clause. I assume that your primary key (the field that uniquely identifies your records) is the ClientCode field.
Then create the connection and the command. Fill the command parameters collection with the parameters required by your text taking the values from the TextBoxes.
Call the ExecuteNonQuery to store the values.
If you succeed then you need to update or reload your datagridview. The best approach would be setting one by one the gridview cells of the current row with the new values from the textboxes, or you could simply extract the code used in form_load to fill the grid and make a new method that you could call from the button click event. (But this could be slower if you have many records)

Update Password in Windows Form C#

I am creating login application (Windows Forms) in C# and using .NET Framework 4.5 with Visual Studio 2012.
I have already entered username and password into database manually.
So in LoginForm, where user enter their username and password my code is like:
public partial class LoginForm : Form
{
public LoginForm()
{
InitializeComponent();
}
System.Data.SqlServerCe.SqlCeConnection con;
System.Data.SqlServerCe.SqlCeDataAdapter da;
DataSet ds1;
int MaxRows = 0;
int inc = 0;
private void go_Click(object sender, EventArgs e)
{
DataRow dRow = ds1.Tables["Users"].Rows[inc];
if (EnterMasterPassword.Text == dRow.ItemArray.GetValue(1).ToString())
{
this.DialogResult = DialogResult.OK;
this.Close();
}
else
MessageBox.Show("Try again");
}
private void LoginForm_Load(object sender, EventArgs e)
{
con = new System.Data.SqlServerCe.SqlCeConnection();
con.ConnectionString = "Data Source=C:\\PMDatabase.sdf";
con.Open();
ds1 = new DataSet();
string sql = "SELECT * From tbl_login";
da = new System.Data.SqlServerCe.SqlCeDataAdapter(sql, con);
da.Fill(ds1, "Users");
MaxRows = ds1.Tables["Users"].Rows.Count;
con.Close();
}
}
*where go is an button*
This works perfectly and users login successfully. But I have no idea how to provide an update/change password functionality to user using Windows Forms. How to update database? And username and password field in it?
So far I have done following procedure:
When user clicks on "Update Password" button a new form (name: Form7) opens which has 3 labels, 3 text-boxes and one button- namely:-
TextBox1--> CurrentPassword
TextBox2--> NewPassword
TextBox3--> ConfirmNewPassword
Button--> UpdateUsrPassword
the code for Form7 is like:-
public partial class Form7 : Form
{
public PasswordsAndData()
{
InitializeComponent();
}
System.Data.SqlServerCe.SqlCeConnection con1;
System.Data.SqlServerCe.SqlCeDataAdapter da1;
DataSet ds2;
int totalPasswords = 0, inc = 0;
private void Form7_Load(object sender, EventArgs e)
{
con1 = new System.Data.SqlServerCe.SqlCeConnection();
con1.ConnectionString = "Data Source=C:\\PMDatabase.sdf";
con1.Open();
ds2 = new DataSet();
string sql = "SELECT * From tbl_UserData";
da1 = new System.Data.SqlServerCe.SqlCeDataAdapter(sql, con1);
da1.Fill(ds2, "UserData");
totalPasswords = ds2.Tables["UserData"].Rows.Count;
con1.Close();
}
private void UpdateUsrPassword_Click(object sender, EventArgs e)
{
if(NewPassword.Text == ConfirmNewPassword.Text)
{
DataRow dRow1 = ds2.Tables["UserData"].NewRow();
dRow1[1] = ConfirmNewPassword.Text;
ds2.Tables["UserData"].Rows.Add(dRow1);
UpdateDB();
MessageBox.Show("Password Updated");
totalPasswords++;
inc = totalPasswords - 1;
}
}
private void UpdateDB()
{
System.Data.SqlServerCe.SqlCeCommandBuilder cb1;
cb1 = new System.Data.SqlServerCe.SqlCeCommandBuilder(da1);
cb1.DataAdapter.Update(ds2.Tables["UserData"]);
}
}
But the above code is not updating the password. How to correct above code? So its works perfectly.
Please guide me.

DataRow dRow1 = ds2.Tables["UserData"].NewRow();
dRow1[1] = ConfirmNewPassword.Text;
ds2.Tables["UserData"].Rows.Add(dRow1);
UpdateDB();
You are adding a row in your UpdateUsrPassword_Click but shouldn't you instead updating the existing row?
You should do:
Get actual password from db
UPDATE of the existing row containing the actual password

instead of adding a row you should use something like this:
dataSet1.Tables["Customers"].Rows[4]["CompanyName"] = "Updated Company Name";
this updates the value in the dataset, which you can then push back to the database.
source with more info on editing values in a dataset:
https://msdn.microsoft.com/en-us/library/tat996zc.aspx

Dataset showing unexpected Data

I have 2 ListBoxes and five textBox. In ListBox_prod i want to retrieve all product (from PRODUCT table) and in Listbox_item i want to retrieve all Items corresponding to the selected Product (from PRODITEM table) on form load event. All the products have more than 1 items associated with them. Problem is with the Listbox_item as it is showing only 1 item. But I want all items to be displayed in Listbox_item when a particulat product is selected. getData() in class DBCommands actually causes the problem. Here's my code:
public partial class form_prodItems : Form
{
private DBCommands dBCommand;
public form_prodItems()
{
InitializeComponent();
listBx_prod.SelectedIndexChanged += new EventHandler(listBx_prod_selValChange);
listBx_item.SelectedIndexChanged += new EventHandler(listBx_item_selValChange);
}
private void form_prodItems_Load(object sender, EventArgs e)
{
// ...
refresh_listBx_prod("PRODUCT", this.listBx_prod, null, null);
refresh_listBx_prod("PRODITEM", this.listBx_item, listBx_prod.ValueMember, listBx_prod.SelectedValue.ToString());
}
private void listBx_item_selValChange(object sender, EventArgs e) // causing problem
{
if (listBx_item.SelectedValue != null)
showPrice("PRODITEM", listBx_item.ValueMember, listBx_item.SelectedValue.ToString());
}
private void listBx_prod_selValChange(object sender, EventArgs e)
{
if(listBx_prod.SelectedValue != null)
refresh_listBx_prod("PRODITEM", this.listBx_item, listBx_prod.ValueMember, listBx_prod.SelectedValue.ToString());
}
private void showPrice(string tblName,string where_column ,string where_val)
{
DataSet ds;
ds = dBCommand.getData("select * from " + tblName + " WHERE " + where_column + " = '" + where_val + "'");
DataRow col_val = ds.Tables[0].Rows[0];
txtBox_12oz.Text = col_val.ItemArray[3].ToString();
txtBox_16oz.Text = col_val.ItemArray[4].ToString();
txtBox_20oz.Text = col_val.ItemArray[5].ToString();
txtBox_1lbs.Text = col_val.ItemArray[6].ToString();
txtBox_2lbs.Text = col_val.ItemArray[7].ToString();
//ds.Clear();
}
private void refresh_listBx_prod(string tblName, ListBox listBox, string where_column, string where_val)
{
DataSet ds = new DataSet();
dBCommand = new DBCommands();
if (where_column == null)
{
ds = dBCommand.getData("SELECT * FROM " + tblName);
}
else
{
ds = dBCommand.getData("SELECT * FROM " + tblName + " WHERE " + where_column + " = " + where_val);
}
listBox.DataSource = ds.Tables[0];
// ds.Clear();
}
}
public class DBCommands
{
private SqlConnection conn;
private SqlDataAdapter dataAdapter;
private DataSet container;
public DataSet getData(string selectCmd)
{
container.Clear(); // I guess something needs to be fixed here some where..
conn = getConnection();
dataAdapter.SelectCommand = new SqlCommand(selectCmd, conn);
dataAdapter.Fill(container);
conn.Close();
return container;
}
private SqlConnection getConnection()
{
SqlConnection retConn = new SqlConnection("Data Source=" + Environment.MachineName + "; Initial Catalog=RESTAURANT; Integrated Security = TRUE");
retConn.Open();
return retConn;
}
}
Actually dataset flushes all data it had got from (SELECT * FROM PRODITEM where PRODUCT_id = '1') and shows data from the last executed query i-e (select * from proditem where item_id = 1)
Any suggestions..

my suggestion is trying to run the command via SqlCommand.
that way you will have better knowledge on what you get back.
use this example:
SqlCommand command = new SqlCommand(selectCmd, conn);
SqlDataReader reader = command.ExecuteReader();
try
{
while (reader.Read())
{
Console.WriteLine(String.Format("{0}, {1}",
reader[0], reader[1]));
}
}
finally
{
// Always call Close when done reading.
reader.Close();
}
and modify it so you'll return a table as you need.
the reason i offer you this is that it's easy to use and you get immediate debug information that help you understand sql mistakes

SqlDataAdapter.Update or SqlCommandBuilder not working

I have a form with a datagrid, which is populated wih data from a sqlserver database. The datagrid populates fine but I am having trouble posting back the changes made by the user, to the table in the sql database. My forms code is as follows:
public partial class frmTimesheet : Form
{
private DataTable tableTS = new DataTable();
private SqlDataAdapter adapter = new SqlDataAdapter();
private int currentTSID = 0;
public frmTimesheet()
{
InitializeComponent();
}
private void frmTimesheet_Load(object sender, EventArgs e)
{
string strUser = cUser.currentUser;
cMyDate cD = new cMyDate(DateTime.Now.ToString());
DateTime date = cD.GetDate();
txtDate.Text = date.ToString();
cboTSUser.DataSource = cUser.GetListOfUsers("active");
cboTSUser.DisplayMember = "UserID";
cboTSUser.Text = strUser;
CheckForTimeSheet();
PopulateTimeSheet();
}
private void CheckForTimeSheet()
{
string strUser = cboTSUser.Text;
cMyDate cD = new cMyDate(txtDate.Text);
DateTime date = cD.GetDate();
int newTSID = cTimesheet.TimeSheetExists(strUser, date);
if (newTSID != this.currentTSID)
{
tableTS.Clear();
if (newTSID == 0)
{
MessageBox.Show("Create TimeSheet");
}
else
{
this.currentTSID = newTSID;
}
}
}
private void PopulateTimeSheet()
{
try
{
string sqlText = "SELECT EntryID, CaseNo, ChargeCode, StartTime, FinishTime, Units " +
"FROM tblTimesheetEntries " +
"WHERE TSID = " + this.currentTSID + ";";
SqlConnection linkToDB = new SqlConnection(cConnectionString.BuildConnectionString());
SqlCommand sqlCom = new SqlCommand(sqlText, linkToDB);
SqlDataAdapter adapter = new SqlDataAdapter(sqlCom);
adapter.SelectCommand = sqlCom;
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
adapter.Fill(tableTS);
dataTimesheet.DataSource = tableTS;
}
catch (Exception eX)
{
string eM = "Error Populating Timesheet";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
}
}
private void txtDate_Leave(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void cboTSUser_DropDownClosed(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void dataTimesheet_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
try
{
adapter.Update(tableTS);
}
catch (Exception eX)
{
string eM = "Error on frmTimesheet, dataTimesheet_CellValueChanged";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
}
}
}
No exception occurs, and when I step through the issue seems to be with the SqlCommandBuilder which does NOT build the INSERT / UPDATE / DELETE commands based on my gien SELECT command.
Can anyone see what I am doing wrong?
What am I missing?

You need to set the UpdateCommand instead of SelectCommand on update:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;

The question is old, but the provided answer by#Anurag Ranjhan need to be corrected.
You need not to write the line:
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
and enough to write:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
//remove the next line
//adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
The Sql update/insert/delete commands are auto generated based on this line
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
You can find the generated update sql by executing the line:
sqlBld.GetUpdateCommand().CommandText;
See the example How To Update a SQL Server Database by Using the SqlDataAdapter Object in Visual C# .NET
The problem said by OP can be checked by reviewing the Sql Statement sent by the client in SQl Server Profiler.