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how fill gridview in foreach

How can I fill a GridView in foreach because this code bring last row just not all.
foreach (int i in userdetails)
{
SqlConnection con = new SqlConnection("*****");
SqlCommand cmd = new SqlCommand("********=" + i, con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
gvSelected.Visible = true;
gvSelected.DataSource = ds;
gvSelected.DataBind();
}

You will want to do something more like this. Only get the data in the loop.
Notice I also used a SqlParameter which is important to prevent SQL Injection and avoid syntax errors.
SqlConnection con = new SqlConnection("*****");
SqlCommand cmd = new SqlCommand("********=#id", con);
SqlParameter parId = new SqlParameter("#id", SqlDbType.Int);
cmd.Parameters.Add(parId);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
foreach (int i in userdetails)
{
parId.Value = i;
da.Fill(ds);
}
gvSelected.Visible = true;
gvSelected.DataSource = ds;
gvSelected.DataBind();
Of course you should consider trying to send all ids at once if possible. You would need something like a Table Valued parameter for that.

Fill combobox from SQL database with specific parameter

I have problem to get specific value from sql server with parameter can anybody explain me why it works on winfom but not on wpf and how i can fix it
my code:
private void UpdateItems()
{
COMBOBOX1.Items.Clear();
SqlConnection conn = new SqlConnection(Properties.Settings.Default.constring.ToString());
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM CLIENT where cod_cli='some_specific_string'", conn);
DataSet ds = new DataSet();
da.Fill(ds, "CLIENT");
COMBOBOX1.ItemsSource = ds.Tables[0].DefaultView;
COMBOBOX1.DisplayMemberPath = ds.Tables[0].Columns["FR"].ToString();
COMBOBOX1.SelectedValuePath = ds.Tables[0].Columns["FC"].ToString();
}
The program when execute this function crash with error:
System.Data.SqlClient.SqlException: 'Invalid column name
'some_specific_string'.'

the solution is
SqlConnection sqlConnection = new SqlConnection(Properties.Settings.Default.constring.ToString());
{
SqlCommand sqlCmd = new SqlCommand("SELECT * FROM CLIENTS where cod_cli=#cod", sqlConnection);
sqlCmd.Parameters.AddWithValue("#cod", cod_cli.Text);
sqlConnection.Open();
SqlDataReader sqlReader = sqlCmd.ExecuteReader();
while (sqlReader.Read())
{
COMBOBOX1.Items.Add(sqlReader["FR"].ToString());
}
sqlReader.Close();
}
The query doesn't recognize string as parameter but adding as SQL parameter it works.

SqlConnection conn = new SqlConnection(Properties.Settings.Default.constring.ToString());
conn.Open();
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM CLIENT where cod_cli='some_specific_string'", conn);
DataSet ds = new DataSet();
da.Fill(ds, "CLIENT");
//Populate the combobox
COMBOBOX1.ItemsSource = ds.Tables[0].DefaultView;
COMBOBOX1.DisplayMemberPath = "FR";
COMBOBOX1.SelectedValuePath = "FC";
where "FR" and "FC" are existing columns in your SELECT Query.

There is already an open DataReader associated with this Connection which must be closed first using c#

I am getting this error "There is already an open DataReader associated with this Connection which must be closed first". I have tried using command but still can't fix this issue. The code I am using is as follows
{
conn.Open();
queryStr = "";
queryStr = "select * from mydata.items;";
cmd = new MySqlCommand(queryStr, conn);
cmd.ExecuteReader();
using (MySqlDataAdapter MyAdapter = new MySqlDataAdapter())
{
MyAdapter.SelectCommand = cmd;
using (DataTable dTable = new DataTable())
{
MyAdapter.Fill(dTable);
GridView1.DataSource = dTable;
}
}
}
I was originally trying below code (without using command).
conn.Open();
queryStr = "";
queryStr = "select * from mydata.items;";
cmd = new MySqlCommand(queryStr, conn);
cmd.ExecuteReader();
MySqlDataAdapter MyAdapter = new MySqlDataAdapter();
MyAdapter.SelectCommand = cmd;
DataTable dTable = new DataTable();
MyAdapter.Fill(dTable);
GridView1.DataSource = dTable;
conn.Close();
But both of the codes are giving exactly the same error (i.e. There is already an open DataReader associated with this Connection which must be closed first.)
Your help would be really appreciated.
Thanks in advance!

Usage of dataset will be more handy and efficient rather than table.Even you can cache it.
Also no need to use using construct because MySqlAdapter's fill method does it everything for you like
i)Open the connection. ii)Read the command ii)Execute the command ii)close the connection
using ()
{
if(Cache["mydata"]==null)
{
queryStr = "";
queryStr = "select * from mydata.items;";
cmd = new MySqlCommand(queryStr, conn);
MySqlDataAdapter MyAdapter = new MySqlDataAdapter();
MyAdapter.SelectCommand = cmd;
DataSet ds =new DataSet();
MyAdapter.Fill(ds);
Cache["mydata"]=ds;
GridView1.DataSource = ds;
GridView1.DataBind();
}
else
{
GridView1.DataSource = (DataSet)Cache["mydata"];
GridView1.DataBind();
}
}

This line creates a DataReader that you're not closing:
cmd.ExecuteReader();
Just remove the whole line, it's useless in your case.

Im trying to load and display a table from sql into my datagrid in C# but its not displaying

//instantiating connection
dbConn = new SqlConnection("Data Source = local host; initial catalog=Project; Integrated Security = SSPI ");
ds = new DataSet();
//select everything from the table
dbCommand = new SqlCommand("SELECT * FROM Shops;", dbConn);
dbAdapter = new SqlDataAdapter(dbCommand);
//filling the datagrid
dbAdapter.Fill(ds, "All Shops");
dataGridView1.DataSource = ds.Tables["All Shops"];

To show data into datagrid you need to assign datasource and then use DataBind() to bind the data.
dataGridView1.DataSource = ds.Tables["All Shops"];
dataGridView1.DataBind(); // use this after assigning the datasource

private void GetResults()
{
//Establishing the MySQL Connection
MySqlConnection conn = new MySqlConnection("Database=potentiality_live;Data Source=eu;User Id=ptly;Password=phat40");
string query;
MySqlCommand SqlCommand;
MySqlDataReader reader;
MySqlDataAdapter adapter = new MySqlDataAdapter();
//Open the connection to db
conn.Open();
//Generating the query to fetch the contact details
query = "SELECT id,date_time,link FROM'sdfsdfsdf'";
SqlCommand = new MySqlCommand(query, conn);
adapter.SelectCommand = new MySqlCommand(query, conn);
//execute the query
reader = SqlCommand.ExecuteReader();
//Assign the results
GridView1.DataSource = reader;
//Bind the data
GridView1.DataBind();
}
Reference:
http://www.codeproject.com/Questions/453091/how-to-get-data-from-sql-database-to-gridview-by-c

datagrid doesn't bind with datatable

I'm working on a webpage in azure. Here's a part of my code:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataTable ds = new DataTable();
_adp.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
}
Off course that instead of "my connection string" there's the real one...
The problem is that the page loads but without the gridview for some reason...
Any help will be great, Thanks
EDIT: I also tried with datasets, like this:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
_adp.Fill(ds);
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind();
}

Try with GridView1.DataSource = ds.Tables[0];
whole code will look as follows:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataSet ds = new DataTable();
_adp.Fill(ds);
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind();
}