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how to make the datagridview load faster with Multiple Row query - c# SQL

The code:
private void suppPopulate()
{
byCode.Text = "Supplier Code";
byDesc.Text = "Supplier";
DGViewListItems.Columns.Add("custcode", "Customer Code");
DGViewListItems.Columns.Add("customer", "Customer");
DGViewListItems.Columns[0].ReadOnly = true;
DGViewListItems.Columns[0].AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells;
DGViewListItems.Columns[1].ReadOnly = true;
DGViewListItems.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill;
using (SqlConnection con = db.Connect())
{
SqlDataReader rd;
SqlCommand cmd = new SqlCommand("SELECT DISTINCT custcode, custname FROM Customers WHERE type = 'V';", db.Connect());
rd = cmd.ExecuteReader();
int i = 0;
if (rd.HasRows)
{
while (rd.Read())
{
DGViewListItems.Rows.Add();
DGViewListItems.Rows[i].Cells["custcode"].Value = rd["custcode"].ToString().Trim();
DGViewListItems.Rows[i].Cells["customer"].Value = rd["custname"].ToString().Trim();
}
}
cmd.Connection.Close();
}
}
The SSMS output:
The output form loads slowly, the rows for the query are over 1000 so I think the cause of the slow load is the number of returned rows? If yes, how do make the load of the datagridview faster?

NOTE - this answer relates to the first part of the original question regarding why only a single row of the DataGrid being populated.
Incrementing the counter "i" at the bottom of the while loop looks like it may fix the problem.
You are adding rows, but only updating the first.

How to show database table data into labels text with loop in c# windows form

I'm facing a problem to show database data into labels. I have a database table name is EMP, EMP has 5 columns, I want all EMP data into labels using a loop. please see the image below for better understanding.
Image:
I write blow code for that but this code the only one row of database table, how I get all rows in labels. Please help...
using (SQLiteConnection conn = new SQLiteConnection(Connection.Conn()))
{
string CommandText = "SELECT * FROM EMP";
using (SQLiteCommand cmd = new SQLiteCommand(CommandText, conn))
{
conn.Open();
SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);
DataSet ds = new DataSet();
sda.Fill(ds);
foreach (DataRow dr in ds.Tables[0].Rows)
{
label1.Text = dr["EmpCode"].ToString();
label2.Text = dr["EmpName"].ToString();
label3.Text = dr["EmpCity"].ToString();
label4.Text = dr["EmpState"].ToString();
}
}
}
Please help me to find the way of showing all data into labels using loop, any code or link will help.

You could do something like this for every label
label1.Text += dr["EmpCode"].ToString() + "<br />";
Or better you should look at datagridview http://csharp.net-informations.com/datagridview/csharp-datagridview-tutorial.htm
I think too that it would be better

A chart element with the name 'John' already exists in the 'SeriesCollection'

I am following this post, to build a bar chart and show on my webpage. Below is the code i have done to accomplish it:
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString);
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "select * from ForChart";
cmd.CommandType = CommandType.Text;
SqlDataAdapter adp = new SqlDataAdapter();
adp.SelectCommand = cmd;
DataSet myDataSet = new DataSet();
adp.Fill(myDataSet, "Query");
foreach (DataRow row in myDataSet.Tables["Query"].Rows)
{
string seriesName = row["SalesRep"].ToString();
Chart1.Series.Add(seriesName);
Chart1.Series[seriesName].ChartType = SeriesChartType.Line;
Chart1.Series[seriesName].BorderWidth = 2;
for (int colIndex = 1; colIndex < myDataSet.Tables["Query"].Columns.Count; colIndex++)
{
string columnName = myDataSet.Tables["Query"].Columns[colIndex].ColumnName;
string YVal = Convert.ToString(row[columnName]);
Chart1.Series[seriesName].Points.AddXY(columnName, YVal);
}
}
GridView1.DataSource = myDataSet;
GridView1.DataBind();
cmd.Connection.Close();
And my table is having the below data. Please check the snapshot
But when i run the code i am getting the below error. Please help me to resolve the issue:
A chart element with the name 'John' already exists in the 'SeriesCollection'.
I am not able to traverse the records thats why i am getting this error, but i don't know how to traverse through all the records.
Coding help would be very much appreciated. Thanks.

I'm assuming that Chart1.Series requires unique names, and thus this call will fail when you try to enter the same name multiple times:
Chart1.Series.Add(seriesName);
Ugh, that entire example on MSDN is filled with bad practices:
select *
no usings used with SqlConnection, SqlCommand,...
mixing UI code and DB code (they should be in separate classes)
Look at this example for a possible solution.

C# SQL multiple query results into diffrent textbox

So I'm having this :
Conn.Open();
SqlCommand Comm3 = new SqlCommand("SELECT answer" + " FROM answers" + " WHERE id_answer=5" , Conn);
SqlDataReader DR3 = Comm3.ExecuteReader();
And there is multiple results,how can I now move each of them in diffrent textbox (i already created textboxes? Till now i only managed to get same result into them.

this is normally how i do it....
SqlConnection cn = new SqlConnection("my connection string");
cn.Open();
string sql = "select * from table where column = whatever";
using (SqlCommand cmd = new SqlCommand(sql,cn))
{
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
myTextBox1.Text = (string)dr["Column1"];
myTextBox2.Text = (string)dr["Column2"];
myTextBox3.Text = (string)dr["Column3"];
}
dr.Close();
}
cn.Close();
just make sure you are aiming the right column name while looping through them, and cast correctly.

You need to loop through each of the item in the Database table. Think of a foreach loop, where you simply just go through each item and work on it similarly.
Here is a sample for that,
// Create new SqlDataReader object and read data from the command.
using (SqlDataReader reader = command.ExecuteReader())
{
// while there is another record present
while (reader.Read())
{
// write the data on to the screen
textBox.Text = reader[0];
}
}
This will add the value of reader's first column (answer) to the textBox. Now make sure you're calling correct textBox to add the value to.
http://www.codeproject.com/Articles/823854/How-to-connect-SQL-Database-to-your-Csharp-program Do give this article a read.

How to iterate through a DataTable

I need to iterate through a DataTable. I have an column there named ImagePath.
When I am using DataReader I do it this way:
SqlDataReader dr = null;
dr = cmd.ExecuteReader();
while (dr.Read())
{
TextBox1.Text = dr["ImagePath"].ToString();
}
How can I achieve the same thing using DataTable?

DataTable dt = new DataTable();
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
adapter.Fill(dt);
foreach(DataRow row in dt.Rows)
{
TextBox1.Text = row["ImagePath"].ToString();
}
...assumes the connection is open and the command is set up properly. I also didn't check the syntax, but it should give you the idea.

foreach (DataRow row in myDataTable.Rows)
{
Console.WriteLine(row["ImagePath"]);
}
I am writing this from memory.
Hope this gives you enough hint to understand the object model.
DataTable -> DataRowCollection -> DataRow (which one can use & look for column contents for that row, either using columnName or ordinal).
-> = contains.

You can also use linq extensions for DataSets:
var imagePaths = dt.AsEnumerble().Select(r => r.Field<string>("ImagePath");
foreach(string imgPath in imagePaths)
{
TextBox1.Text = imgPath;
}

There are already nice solution has been given. The below code can help others to query over datatable and get the value of each row of the datatable for the ImagePath column.
for (int i = 0; i < dataTable.Rows.Count; i++)
{
var theUrl = dataTable.Rows[i]["ImagePath"].ToString();
}

The above examples are quite helpful. But, if we want to check if a particular row is having a particular value or not. If yes then delete and break and in case of no value found straight throw error. Below code works:
foreach (DataRow row in dtData.Rows)
{
if (row["Column_name"].ToString() == txtBox.Text)
{
// Getting the sequence number from the textbox.
string strName1 = txtRowDeletion.Text;
// Creating the SqlCommand object to access the stored procedure
// used to get the data for the grid.
string strDeleteData = "Sp_name";
SqlCommand cmdDeleteData = new SqlCommand(strDeleteData, conn);
cmdDeleteData.CommandType = System.Data.CommandType.StoredProcedure;
// Running the query.
conn.Open();
cmdDeleteData.ExecuteNonQuery();
conn.Close();
GetData();
dtData = (DataTable)Session["GetData"];
BindGrid(dtData);
lblMsgForDeletion.Text = "The row successfully deleted !!" + txtRowDeletion.Text;
txtRowDeletion.Text = "";
break;
}
else
{
lblMsgForDeletion.Text = "The row is not present ";
}
}

foreach(DataGridViewRow row in dataGridView1){ var a = row.Cells[4].Value.ToString(); }