Loko Loko - 1 month ago 16
C# Question

Oracle database table in gridview

I want to get the result from a query in my oracle database and put it in a gridview. Now my problem is, I have no idea how to output it in the gridview. I am using the gridview from the toolbox and my oracle connection is working. I also have the right

SELECT
query and I can output that in a listbox. I just have no idea how to do this in a gridview. I looked for it and I came across this: How to populate gridview with mysql? Although this doesn't help me.

How can I output it in a gridview so that it looks exactly the same as a normal table in the oracle database?

What should I use and how?

This is my code:

public void read()
{
try
{
var conn = new OracleConnection("")
conn.Open();
OracleCommand cmd = new OracleCommand("select * from t1", conn);
OracleDataReader reader = cmd.ExecuteReader();
DataTable dataTable = new DataTable();
while (reader.Read())
{
var column1 = reader["vermogen"];
column = (column1.ToString());
listBox1.Items.Add(column);
}
conn.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}

}

Answer

To bind a DataTable to a DataGridView your code need simply to be changed to

    public void read()
    {
        try
        {
            using(OracleConnection conn = new OracleConnection("....."))
            using(OracleCommand cmd = new OracleCommand("select * from t1", conn))
            {
                conn.Open();
                using(OracleDataReader reader = cmd.ExecuteReader())
                {
                     DataTable dataTable = new DataTable();
                     dataTable.Load(reader);
                     dataGridView1.DataSource = dataTable;
                }
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }
 }

The OracleDataReader could be passed to the Load method of the DataTable and then the table is ready to be bound to the DataGridView DataSource property. I have also added some using statement to ensure proper disposing of the disposable objects employed. (In particular the OracleConnection is very expensive to not close in case of exceptions)