Populate Combobox from Database Using the WebService in C# Winforms - c#

Here Is My Code :
[WebMethod]
public SqlDataReader Cmb_BranchMaster() {
SqlCommand ad1 = new SqlCommand("select * from BranchMaster", conn);
if (conn.State == ConnectionState.Open)
conn.Close();
conn.Open();
SqlDataReader rdr2 = ad1.ExecuteReader();
if (rdr2.HasRows)
{
while (rdr2.Read())
{
// here cmbranchname is my combobox of winforms .. so here in webservice it gievs error
cmbBranchName.Items.Add(rdr2[1].ToString());
}
}
conn.Close();
}
now what to do to return the data and use in my winform

Here is the Solution i Got
Web Service code
static SqlConnection conn = new SqlConnection(ConfigurationSettings.AppSettings["Connection"].ToString());
[WebMethod]
public DataSet Cmb_BranchMaster()
{
conn.Open();
SqlCommand ad1 = new SqlCommand("select * from BranchMaster", conn);
SqlDataAdapter adapt = new SqlDataAdapter(ad1);
DataSet ds = new DataSet();
adapt.Fill(ds);
conn.Close();
return ds;
}
Winform Code
private void ComboBox_Load(object sender, EventArgs e)
{
myservice.Service test = new myservice.Service();
DataSet dd = new DataSet();
dd = test.Cmb_BranchMaster();
comboBox1.DataSource = dd.Tables[0];
comboBox1.DisplayMember = "BranchName";
comboBox1.ValueMember = "BranchID";
}

Related

In drop down, all values are showing from column. need only one time value

DropDownList needs only one value for one time.
This is my code:
SqlConnection con = new SqlConnection("data source=.;initial catalog=Rupesh;integrated security=true");
SqlCommand cmd;
SqlDataAdapter da;
string query;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
con.Open();
query = "select * from vendor";
cmd = new SqlCommand(query, con);
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
DropDownList1.Items.Add(dr[4].ToString());
}
con.Close();
vendordetails();
}
}
private void vendordetails()
{
try
{
con.Open();
query = "select * from vendor";
cmd = new SqlCommand(query, con);
da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
}
catch (Exception ex)
{
Response.Write(ex.Message);
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
try
{
con.Open();
query = "select * from vendor where vendor_name='" + DropDownList1.SelectedItem.ToString() + "'";
cmd = new SqlCommand(query, con);
da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
}
catch (Exception ex)
{
Response.Write(ex.Message);
}
}
Instead of using
"select * from vendor"
use something like
"select [columnname] from vendor"
Replace [columnname] with the name of the column you want to display.
The * gets you all values from all columns from the database.
I think instead of
if (!IsPostBack)
{
query = "select * from vendor";
}
you need
if (!IsPostBack)
{
query = "select distinct vendor_name from vendor";
}
Now I am assuming that when you select a Vendor from the Drop down, you want to see the vendor details in the grid.
You seem to be not far off......
Adjust your proc vendordetails() to be.............
private void vendordetails(string vendorName = "")
{
try
{
con.Open();
query = String.Format( "select * from vendor where vendor_name = \'{0}\'", vendorName);
cmd = new SqlCommand(query, con);
da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
}
catch (Exception ex)
{
Response.Write(ex.Message);
}
}
Then in DropDownList1_SelectedIndexChanged simply have....
vendordetails(DropDownList1.SelectedItem.Text)

Gridview not binding and showing datas from my database

well, I've done everything on my behalf just to solve this problem. i'm trying to print the data from my database using grid view in asp.net using c# codes. can anyone tell me whats wrong and how to improve my codes. thank you.
using (MySqlConnection con = new MySqlConnection(ConfigurationManager.ConnectionStrings["DBCon"].ConnectionString))
{
constructor var = new constructor();
con.Open();
string sql = "SELECT first_name,last_name,username,contact_number,address,email FROM user_tbl WHERE user_type='2'";
MySqlCommand cmd = new MySqlCommand(sql, con);
MySqlDataReader reader1 = cmd.ExecuteReader();
reader1.Close();
try
{
MySqlDataAdapter da = new MySqlDataAdapter(cmd);
DataSet ds = new DataSet();
GridView1.DataSource = ds;
GridView1.DataBind();
}
catch (Exception ex)
{
lblresult.Text = "ERROR>>" + ex.Message + "!";
}
finally
{
con.Close();
sql = null;
}
You must fill the DataSet with data like this :
MySqlDataAdapter da = new MySqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds, "TableName");
GridView1.DataSource = ds.Tables["TableName"];
GridView1.DataBind();
You're assigning an empty DataSet to your DataSource, without filling the results of your DataReader into the DataSet/DataTable.
using (MySqlConnection con = new MySqlConnection(""))
{
con.Open();
string sql = "SELECT first_name,last_name,username,contact_number,address,email FROM user_tbl WHERE user_type='2'";
MySqlCommand cmd = new MySqlCommand(sql, con);
try
{
DataTable dt = new DataTable();
using (MySqlDataReader reader1 = cmd.ExecuteReader())
{
dt.Load(reader1);
}
GridView1.DataSource = dt ;
GridView1.DataBind();
}
catch (Exception ex)
{
lblresult.Text = "ERROR>>" + ex.Message + "!";
}
finally
{
con.Close();
sql = null;
}
}

What is the way to populate a dropdownlist from a database in asp.net by using classes?

I am trying to populate a dropdownlist from sql server by using classes as shown below. The code breaks down when it comes to bind the data into the dropdown list. It gives an error on giving the dropdownlist the dataValueField and datatTextField.
HTML... a.aspx
<asp:DropDownList ID="NationalityDropDownList" runat="server" >
</asp:DropDownList>
C#... a.aspx.cs
protected void Page_Load(object sender, EventArgs e)
{
Classes.Nationality PossibleNationality = new Classes.Nationality();
if (!Page.IsPostBack)
{
DataTable dataTable = PossibleNationality.getNationality();
NationalityDropDownList.DataSource = dataTable;
NationalityDropDownList.DataValueField = "ID";
NationalityDropDownList.DataTextField = "Nationality";
NationalityDropDownList.DataBind();
}
}
Nationality.cs
public class Nationality
{
public DataTable getNationality()
{
SqlConnection conn;
SqlCommand comm;
string connectionString = ConfigurationManager.ConnectionStrings["InformationConnection"].ConnectionString;
conn = new SqlConnection(connectionString);
comm = new SqlCommand("spGetAllUsers", conn);
comm.CommandType = CommandType.StoredProcedure;
DataTable dataTable;
try
{
conn.Open();
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = comm;
dataTable = new DataTable();
da.Fill(dataTable);
}
finally
{
conn.Close();
}
return dataTable;
}
}
SQL procedure....
ALTER PROCEDURE [dbo].[spGetNationalities]
AS
BEGIN
select * from Nationality;
END
This line of code in your getNationalitymethod...
comm = new SqlCommand("spGetAllUsers", conn);
...should be this instead
comm = new SqlCommand("spGetNationalities", conn);
Databinding should work if your Nationality table has columns ID and Nationality
if (!Page.IsPostBack)
{
try
{
using (SqlConnection con = new SqlConnection("Data Source = NIPOON; Initial Catalog = CustomerOrders; Integrated Security = true"))
{
SqlCommand cmd = new SqlCommand("SELECT Name FROM Customer", con);
con.Open();
dropDownList.DataSource = cmd.ExecuteReader();
dropDownList.DataTextField = "Name";
dropDownList.DataValueField = "Name";
dropDownList.DataBind();
}
}
catch (Exception Ex)
{
Console.WriteLine("Error: " + Ex.Message);
}
GetData();
}

Populate a datagridview with sql query results

I'm trying to present query results, but I keep getting a blank data grid.
It's like the data itself is not visible
Here is my code:
private void Employee_Report_Load(object sender, EventArgs e)
{
string select = "SELECT * FROM tblEmployee";
Connection c = new Connection();
SqlDataAdapter dataAdapter = new SqlDataAdapter(select, c.con); //c.con is the connection string
SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);
DataTable table = new DataTable();
table.Locale = System.Globalization.CultureInfo.InvariantCulture;
dataAdapter.Fill(table);
bindingSource1.DataSource = table;
dataGridView1.ReadOnly = true;
dataGridView1.DataSource = bindingSource1;
}
What's wrong with this code?
Here's your code fixed up. Next forget bindingsource
var select = "SELECT * FROM tblEmployee";
var c = new SqlConnection(yourConnectionString); // Your Connection String here
var dataAdapter = new SqlDataAdapter(select, c);
var commandBuilder = new SqlCommandBuilder(dataAdapter);
var ds = new DataSet();
dataAdapter.Fill(ds);
dataGridView1.ReadOnly = true;
dataGridView1.DataSource = ds.Tables[0];
String strConnection = Properties.Settings.Default.BooksConnectionString;
SqlConnection con = new SqlConnection(strConnection);
SqlCommand sqlCmd = new SqlCommand();
sqlCmd.Connection = con;
sqlCmd.CommandType = CommandType.Text;
sqlCmd.CommandText = "Select * from titles";
SqlDataAdapter sqlDataAdap = new SqlDataAdapter(sqlCmd);
DataTable dtRecord = new DataTable();
sqlDataAdap.Fill(dtRecord);
dataGridView1.DataSource = dtRecord;
You don't need bindingSource1
Just set dataGridView1.DataSource = table;
Try binding your DataGridView to the DefaultView of the DataTable:
dataGridView1.DataSource = table.DefaultView;
This is suppose to be the safest and error pron query :
public void Load_Data()
{
using (SqlConnection connection = new SqlConnection(DatabaseServices.connectionString)) //use your connection string here
{
var bindingSource = new BindingSource();
string fetachSlidesRecentSQL = "select top (50) * from dbo.slides order by created_date desc";
using (SqlDataAdapter dataAdapter = new SqlDataAdapter(fetachSlidesRecentSQL, connection))
{
try
{
SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);
DataTable table = new DataTable();
dataAdapter.Fill(table);
bindingSource.DataSource = table;
recent_slides_grd_view.ReadOnly = true;
recent_slides_grd_view.DataSource = bindingSource;
}
catch (SqlException ex)
{
MessageBox.Show(ex.Message.ToString(), "ERROR Loading");
}
finally
{
connection.Close();
}
}
}
}
You may get a blank data grid if you set the data Source to a Dataset that you added to the form but is not being used. Set this to None if you are programatically setting your dataSource based on the above codes.
You may try this sample, and always check your Connection String, you can use this example with or with out bindingsource you can load the data to datagridview.
private void Employee_Report_Load(object sender, EventArgs e)
{
var table = new DataTable();
var connection = "ConnectionString";
using (var con = new SqlConnection { ConnectionString = connection })
{
using (var command = new SqlCommand { Connection = con })
{
if (con.State == ConnectionState.Open)
{
con.Close();
}
con.Open();
try
{
command.CommandText = #"SELECT * FROM tblEmployee";
table.Load(command.ExecuteReader());
bindingSource1.DataSource = table;
dataGridView1.ReadOnly = true;
dataGridView1.DataSource = bindingSource1;
}
catch(SqlException ex)
{
MessageBox.Show(ex.Message + " sql query error.");
}
}
}
}
you have to add the property Tables to the DataGridView Data Source
dataGridView1.DataSource = table.Tables[0];
if you are using mysql this code you can use.
string con = "SERVER=localhost; user id=root; password=; database=databasename";
private void loaddata()
{
MySqlConnection connect = new MySqlConnection(con);
connect.Open();
try
{
MySqlCommand cmd = connect.CreateCommand();
cmd.CommandText = "SELECT * FROM DATA1";
MySqlDataAdapter da = new MySqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
datagrid.DataSource = dt;
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
}
Years late but here's the simplest for others in case.
String connectionString = #"Data Source=LOCALHOST;Initial Catalog=DB;Integrated Security=true";
SqlConnection cnn = new SqlConnection(connectionString);
SqlDataAdapter sda = new SqlDataAdapter("SELECT * FROM tblEmployee;", cnn);
DataTable data = new DataTable();
sda.Fill(data);
DataGridView1.DataSource = data;
Using DataSet is not necessary and DataTable should be good enough. SQLCommandBuilder is unnecessary either.
I think this professional way to Write from start, but you can use this code with MySQL bout I think they both are the same:
1/
using System.Data; AND using MySql.Data.MySqlClient;
2/
MySqlConnection con = new MySqlConnection("datasource=172.16.2.104;port=3306;server=localhost;database=DB_Name=root;password=DB_Password;sslmode=none;charset=utf8;");
MySqlCommand cmd = new MySqlCommand();
3/
public void SetCommand(string SQL)
{
cmd.Connection = con;
cmd.CommandText = SQL;
}
private void FillGrid()
{
SetCommand("SELECT * FROM `transport_db`ORDER BY `id` DESC LIMIT 15");
DataTable tbl = new DataTable();
tbl.Load(cmd.ExecuteReader());
dataGridView1.DataSource = tbl;
}
for oracle:
var connString = new ConfigurationBuilder().AddJsonFile("AppSettings.json").Build()["ConnectionString"];
OracleConnection connection = new OracleConnection();
connection.ConnectionString = connString;
connection.Open();
var dataAdapter = new OracleDataAdapter("SELECT * FROM TABLE", connection);
var dataSet = new DataSet();
dataAdapter.Fill(dataSet);

Question about showing sql server data in a tabbed view

I am creating a inventory app using c# that pulls its info from sql server. I am making it a tabbed view, with each tab representing a different type of item. I have included some of my code, what I am trying to figure is, is there a better way to do this? I dont feel like the way I am doing is right, even though it works. All my queries for each tab are stored procedures. Secondly, How would I insert and update the database through the grid?
public partial class InventoryWindow : Window
{
private InventoryDS InvDS;
private String connString = "server=PC-server;database=Inventory;user=user;password=password";
String sqlString_Routers = InventoryOutputQuery.InventorySummary_Routers();
public InventoryWindow()
{
InitializeComponent();
if (dgDataView != null)
{
SqlConnection con = new SqlConnection(connString);
SqlDataAdapter adpt = new SqlDataAdapter(sqlString_Routers, con);
DataSet ds = new DataSet();
adpt.Fill(ds, sqlString_Routers);
dgDataView.DataContext = ds;
}
}
private void showTaps()
{
String sqlString_Taps = InventoryOutputQuery.InventorySummary_Routers();
SqlConnection con = new SqlConnection(connString);
con.Open();
SqlCommand cmd = new SqlCommand(sqlString_Routers, con);
SqlDataReader dr = cmd.ExecuteReader();
DataTable dt = new DataTable();
dt.Load(dr);
dgDataView.DataContext = dt;
con.Close();
}
private void showPower()
{
String sqlString_Power = InventoryOutputQuery.InventorySummary_Power();
SqlConnection con = new SqlConnection(connString);
con.Open();
SqlCommand cmd = new SqlCommand(sqlString_Power, con);
SqlDataReader dr = cmd.ExecuteReader();
DataTable dt = new DataTable();
dt.Load(dr);
dgDataView.DataContext = dt;
con.Close();
}
private void showSwitches()
{
String sqlString_Switches = InventoryOutputQuery.InventorySummary_Switches();
SqlConnection con = new SqlConnection(connString);
con.Open();
SqlCommand cmd = new SqlCommand(sqlString_Switches, con);
SqlDataReader dr = cmd.ExecuteReader();
DataTable dt = new DataTable();
dt.Load(dr);
dgDataView.DataContext = dt;
con.Close();
}
And below is how i bind it to the grid:
public void BindGrid(string view)
{
switch (view.ToUpper())
{
case "Routers":
showTaps();
break;
case "POWER":
showPower();
break;
case "SWITCHES":
showSwitches();
break;
case "HUBS":
showHubs();
private void tcDataView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
TabItem ti = tcDataView.SelectedItem as TabItem;
if (ti != null)
BindGrid(ti.Header.ToString());
}
break;
My suggestion is to be careful with how we handle SqlConnection. It is a scarce resource and it will run out pretty soon if we are not careful.
Please wrap sql code in a using block, for example:
using (SqlConnection con = new SqlConnection(connString))
{
SqlDataAdapter adpt = new SqlDataAdapter(sqlString_Routers, con);
DataSet ds = new DataSet();
adpt.Fill(ds, sqlString_Routers);
dgDataView.DataContext = ds;
}
The following link will explain the effect of 'using' block in a bit more details.
http://www.codeproject.com/KB/cs/tinguusingstatement.aspx

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