[c#] how to bind datatable to datagridview in c#

I need to bind my DataTable to my DataGridView. i do this:

        DTable = new DataTable();
        SBind = new BindingSource();
        //ServersTable - DataGridView
        for (int i = 0; i < ServersTable.ColumnCount; ++i)
        {
            DTable.Columns.Add(new DataColumn(ServersTable.Columns[i].Name));
        }

        for (int i = 0; i < Apps.Count; ++i)
        {
            DataRow r = DTable.NewRow();
            r.BeginEdit();
            foreach (DataColumn c in DTable.Columns)
            {
                r[c.ColumnName] = //writing values
            }
            r.EndEdit();
            DTable.Rows.Add(r);
        }
        SBind.DataSource = DTable;
        ServersTable.DataSource = SBind;

But all i got is DataTable ADDS NEW columns to my DataGridView. I don't need this, i just need to write under existing columns.

foreach (DictionaryEntry entry in Hashtable)
{
    datagridviewTZ.Rows.Add(entry.Key.ToString(), entry.Value.ToString());
}

private void Form1_Load(object sender, EventArgs e)
    {
        DataTable StudentDataTable = new DataTable("Student");

        //perform this on the Load Event of the form
        private void AddColumns() 
        {
            StudentDataTable.Columns.Add("First_Int_Column", typeof(int));
            StudentDataTable.Columns.Add("Second_String_Column", typeof(String));

            this.dataGridViewDisplay.DataSource = StudentDataTable;
        }
    }

    //Save_Button_Event to save the form field to the table which is then bind to the TableGridView
    private void SaveForm()
        {
            StudentDataTable.Rows.Add(new object[] { textBoxFirst.Text, textBoxSecond.Text});

            dataGridViewDisplay.DataSource = StudentDataTable;
        }

for example we want to set a DataTable 'Users' to DataGridView by followig 2 steps : step 1 - get all Users by :

public DataTable  getAllUsers()
    {
        OracleConnection Connection = new OracleConnection(stringConnection);
        Connection.ConnectionString = stringConnection;
        Connection.Open();

        DataSet dataSet = new DataSet();

        OracleCommand cmd = new OracleCommand("semect * from Users");
        cmd.CommandType = CommandType.Text;
        cmd.Connection = Connection;

        using (OracleDataAdapter dataAdapter = new OracleDataAdapter())
        {
            dataAdapter.SelectCommand = cmd;
            dataAdapter.Fill(dataSet);
        }

        return dataSet.Tables[0];
    }

step 2- set the return result to DataGridView :

public void setTableToDgv(DataGridView DGV, DataTable table)
    {
        DGV.DataSource = table;
    }

using example:

    setTableToDgv(dgv_client,getAllUsers());

Even better:

DataTable DTable = new DataTable();
BindingSource SBind = new BindingSource();
SBind.DataSource = DTable;
DataGridView ServersTable = new DataGridView();

ServersTable.AutoGenerateColumns = false;
ServersTable.DataSource = DTable;

ServersTable.DataSource = SBind;
ServersTable.Refresh();

You're telling the bindable source that it's bound to the DataTable, in-turn you need to tell your DataGridView not to auto-generate columns, so it will only pull the data in for the columns you've manually input into the control... lastly refresh the control to update the databind.

On the DataGridView, set the DataPropertyName of the columns to your column names of your DataTable.

// I built my datatable first, and populated it, columns, rows and all. //Then, once the datatable is functional, do the following to bind it to the DGV. NOTE: the DGV's AutoGenerateColumns property must be 'true' for this example, or the "assigning" of column names from datatable to dgv will not work. I also "added" my datatable to a dataset previously, but I don't think that is necessary.

 BindingSource SBind = new BindingSource();
 SBind.DataSource = dtSourceData;

 ADGView1.AutoGenerateColumns = true;  //must be "true" here
 ADGView1.Columns.Clear();
 ADGView1.DataSource = SBind;

 //set DGV's column names and headings from the Datatable properties
 for (int i = 0; i < ADGView1.Columns.Count; i++)
 {
       ADGView1.Columns[i].DataPropertyName = dtSourceData.Columns[i].ColumnName;
       ADGView1.Columns[i].HeaderText = dtSourceData.Columns[i].Caption;
 }
 ADGView1.Enabled = true;
 ADGView1.Refresh();