Clearing data in SqlDataAdapter - c#

I'm using SQLDataAdapter to populate data from my SQL server database in 2 DropDownLists. Depending on what is selected in the first dropdown, the corresponding data is populated in the second. It works fine but data that has since been deleted by the admin on their side of the application and is no longer in the database is still showing up in the dropdowns.
Is there a way in which I can reset or clear what is already in the DataAdapter, refresh it and then show only the current data?
If it helps here is how I have the data binding to the dropdowns. Firstly a general method which is called on page load to populate the first dropdown, and again in the _SelectedIndexChanged of the first dropdown to bind the relevant data to the second.
if (!IsPostBack)
{
DataBind();
string query = "select Distinct ClubID, ClubName from Pitch";
BindDropDownList(DDLClub, query, "ClubName", "ClubID", "Select Club");
DDLPitches.Enabled = false;
DDLPitches.Items.Insert(0, new ListItem("Select Pitch", "0"));
}
private void BindDropDownList(DropDownList DDL, string query, string text, string value, string defaultText)
{
string ConnString = ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString;
SqlCommand cmd = new SqlCommand(query);
using (SqlConnection con = new SqlConnection(ConnString))
{
using (SqlDataAdapter sda = new SqlDataAdapter())
{
cmd.Connection = con;
con.Open();
DDL.DataSource = cmd.ExecuteReader();
DDL.DataTextField = text;
DDL.DataValueField = value;
DDL.DataBind();
sda.Dispose();
con.Close();
}
}
DDL.Items.Insert(0, new ListItem(defaultText, "0"));
}
protected void DDLClub_SelectedIndexChanged(object sender, EventArgs e)
{
DDLPitches.Enabled = false;
DDLPitches.Items.Clear();
DDLPitches.Items.Insert(0, new ListItem("Select Pitch", "0"));
int ClubID = int.Parse(DDLClub.SelectedItem.Value);
if (ClubID > 0)
{
string query = string.Format("select PitchID, ClubID, ClubName, PitchName from Pitch where ClubID = {0}", ClubID);
BindDropDownList(DDLPitches, query, "PitchName", "PitchID", "Select Pitch");
DDLPitches.Enabled = true;
}
}

Related

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();
}
}
}
}
}

ComboBox with Suggest Ability based on Substring-Search or text match in list items of combox

This is how I am populating my combobox from database which is large quantity.
How i am search from list items in combobox as suggested not start from beginning it search also substring found inside of the string. and show all matching results in suggested list of combobox
{
SqlConnection connection = DBConnectivity.getConnection();
SqlCommand command;
string query;
DataSet dataset;
DataTable datatable;
SqlDataAdapter adapter;
SqlDataReader reader;
string[] ProductNameList;
public productform()
{
InitializeComponent();
}
//------------Form load Events and functions-----------------------------
DataSet dataset2 = new DataSet();
ClassesAll.PartyandProductClass PartyandProducts = new ClassesAll.PartyandProductClass();
private void productform_Load(object sender, EventArgs e)
{
try
{
// events for loading partytype broker on load
string query2 = "SELECT productNameUR, id FROM product";
SqlCommand command2 = DBConnectivity.getCommandForQuery(query2, connection);
SqlDataAdapter adapter2 = new SqlDataAdapter(command2);
adapter2.Fill(dataset2);
int result = command2.ExecuteNonQuery();
this.cBjins.DisplayMember = "productNameUR";
this.cBjins.ValueMember = "id";
DataRow datarow1 = dataset2.Tables[0].NewRow();
datarow1["productNameUR"] = "Select Product";
dataset2.Tables[0].Rows.InsertAt(datarow1, 0);
this.cBjins.DataSource = dataset2.Tables[0];
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Suggest me a solution.

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.

Fill ComboBox with Access DB data

I'm using Visual Studio 2010 and C# to create a windows form with a combobox that should contain employees initials. I have spent the last few days searching through every solution I can find and I still can not get my combobox to populate.
This is what I've got as of now:
public static void FillComboBox(string Query, System.Windows.Forms.ComboBox LoggedByBox)
{
using (var CONN = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\Users\\Documents\\Service Request Application\\bin\\Debug\\servicereq1.mdb"))
{
CONN.Open();
DataTable dt = new DataTable();
try
{
OleDbCommand cmd = new OleDbCommand(Query, CONN);
OleDbDataReader myReader = cmd.ExecuteReader();
dt.Load(myReader);
}
catch (OleDbException e)
{
Console.WriteLine(e.ToString());
Console.ReadLine();
return;
}
LoggedByBox.DataSource = dt;
LoggedByBox.ValueMember = "ID";
LoggedByBox.DisplayMember = "Initials";
}
}
Then I call it when the form loads
private void Form1_Load(object sender, EventArgs e)
{
FillComboBox("select ID, Initials from [Fixers and Testers]", LoggedByBox);
}
When I run the program, the combobox is still blank. I'm positive that my column names and table names are correct. Any suggestions?
I finally got my ComboBox filled and I wanted to share what I changed for anyone else who stumbles across this question in their searches. After spending a bit more time searching through other questions and MSDN, I was able to come up with this.
private void LoadComboLogged()
{
AppDomain.CurrentDomain.SetData("DataDirectory",#"\\prod\ServiceRequests");
string strCon = #"Provider=Microsoft.Jet.OLEDB.4.0;DataSource=|DataDirectory|\servicereq1.mdb";
try
{
using (OleDbConnection conn = new OleDbConnection(strCon))
{
conn.Open();
string strSql = "SELECT Initials FROM [Fixers and Testers] WHERE [Status] ='C'";
OleDbDataAdapter adapter = new OleDbDataAdapter(new OleDbCommand(strSql, conn));
DataSet ds = new DataSet();
adapter.Fill(ds);
loggedByComboBox.DataSource = ds.Tables[0];
loggedByComboBox.DisplayMember = "Initials";
loggedByComboBox.ValueMember = "Initials";
}
}
catch (Exception ex)
{
}
}
I also found that I needed to call
LoadComboLogged();
when I initialized my form. Without that line, the ComboBox would only show a blank dropdown list. Hope this helps someone else who runs into this problem.
Passing control to static method causing this issue. Instead of passing control to the method make that method returns the table and within the load method load the control.
SqlConnection con = new SqlConnection("Data Source=RUSH-PC\\RUSH;Initial Catalog=Att;Integrated Security=True");
con.Open();
SqlDataAdapter da = new SqlDataAdapter("select name from userinfo", con);
DataTable dt = new DataTable();
da.Fill(dt);
DataRow dr;
dr = dt.NewRow();
dt.Rows.InsertAt(dr, 1);
comboBox1.DisplayMember = "name";
comboBox1.ValueMember = "name";
comboBox1.DataSource = dt;
con.Close();
This may help you...
Good luck...:-)
Another possible solution would be to query and return a list of strings. Perhaps it may be less efficient, but it's what I used in a recent project of mine. Here's an example that would reside in a method, possibly called GetInitialsFromDatabase():
using(var conn = new MySqlConnection(connectionString)
{
conn.Open();
using(MySqlCommand cmd = new MySqlCommand())
{
cmd.Connection = conn;
cmd.CommandText = "SELECT Initials FROM [Fixers and Testers] WHERE [Status] ='C'";
MySqlDataReader reader = cmd.ExecuteReader();
while(reader.Read())
{
// initials is a List<String> previously defined (Assuming strings)
initials.Add(String.Format("{0}", reader[0]));
}
}
conn.Close();
}
And then return the initials List, and then in your GUI you could say:
comboBox1.DataSource = returnedList;
comboBox1.DropDownStyle = ComboBoxStyle.DropDownList;

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