DataGridView.RowsAdded Event
Assembly: System.Windows.Forms (in system.windows.forms.dll)
Rows in the control are not automatically sorted when new rows are added. To sort new rows into their correct position, call the Sort method in a RowsAdded event handler.
When the user adds a new row using the row for new records, the DataGridViewRowsAddedEventArgs.RowIndex value in the handler for this event is equal to the index of the new location of the row for new records, which is one greater than the row just added. When you add rows programmatically, however, the RowIndex value is the index of the first row added.
In virtual mode, this event occurs before the CellValuePushed event and can be used to create new records in your data store that you can then populate in the CellValuePushed event handler.
For more information about handling events, see Consuming Events.
The following code example handles the RowsAdded event to increment the number of rows in a virtual DataGridView. The number of rows is used in the CellValueNeeded handler so it knows when to show a blank cell versus an initialized cell for a new row. This example is part of a larger example available in the VirtualMode reference topic.
bool newRowNeeded; private void dataGridView1_NewRowNeeded(object sender, DataGridViewRowEventArgs e) { newRowNeeded = true; } const int initialSize = 5000000; int numberOfRows = initialSize; private void dataGridView1_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e) { if (newRowNeeded) { newRowNeeded = false; numberOfRows = numberOfRows + 1; } } #region "data store maintance" const int initialValue = -1; private void dataGridView1_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e) { if (store.ContainsKey(e.RowIndex)) { // Use the store if the e value has been modified // and stored. e.Value = store[e.RowIndex]; } else if (newRowNeeded && e.RowIndex == numberOfRows) { if (dataGridView1.IsCurrentCellInEditMode) { e.Value = initialValue; } else { // Show a blank value if the cursor is just resting // on the last row. e.Value = String.Empty; } } else { e.Value = e.RowIndex; } } private void dataGridView1_CellValuePushed(object sender, DataGridViewCellValueEventArgs e) { store.Add(e.RowIndex, int.Parse(e.Value.ToString())); } #endregion private Dictionary<int, int> store = new Dictionary<int, int>();
private boolean newRowNeeded;
private void dataGridView1_NewRowNeeded(Object sender,
DataGridViewRowEventArgs e)
{
newRowNeeded = true;
} //dataGridView1_NewRowNeeded
private final int INITIALSIZE = 5000000;
private int numberOfRows = INITIALSIZE;
private void dataGridView1_RowsAdded(Object sender,
DataGridViewRowsAddedEventArgs e)
{
if (newRowNeeded) {
newRowNeeded = false;
numberOfRows = numberOfRows + 1;
}
} //dataGridView1_RowsAdded
#region "data store maintance"
private final int INITIALVALUE = -1;
private void dataGridView1_CellValueNeeded(Object sender,
DataGridViewCellValueEventArgs e)
{
if (store.ContainsKey(e.get_RowIndex())) {
// Use the store if the e value has been modified
// and stored.
e.set_Value((Int32)store.get_Item(e.get_RowIndex()));
}
else {
if (newRowNeeded && e.get_RowIndex() == numberOfRows) {
if (dataGridView1.get_IsCurrentCellInEditMode()) {
e.set_Value((Int32)INITIALVALUE);
}
else {
// Show a blank e if the cursor is just loitering
// over(the)
// last row.
e.set_Value("");
}
}
else {
e.set_Value((Int32)e.get_RowIndex());
}
}
} //dataGridView1_CellValueNeeded
private void dataGridView1_CellValuePushed(Object sender,
DataGridViewCellValueEventArgs e)
{
store.Add(e.get_RowIndex(), Int32.Parse(e.get_Value().ToString()));
} //dataGridView1_CellValuePushed
#endregion
private Dictionary<int, int> store = new Dictionary<int, int>();
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.