I'm adding a great deal of rows to a data grid view, and the process is pretty slow because it appears to try to redraw after each addition.
I'm having trouble finding an example online of how to create a List (or array, whichever works) of rows and add them all at once after the list is created. I need to do this to stop it from re-drawing after each addition though.
Can anyone provide a brief example of this or point me to a good doc?
Here are a couple of ideas:
1) Bind a list to the DataGridView. When you set the DataGridView.DataSource = MyList, it immediately updates the entire grid without all the line-by-line action. You can add the items to MyList and then rebind to the DataGridView. (I prefer using a BindingList which will update the DataGridView grid dynamically.)
2) If data binding is not an option, what I've done in the past is set the AutoSizeMode = NotSet for each column before the update and then set it back to whatever it was before. It is the AutoSizeMode that really slows down the drawing.
You're probably looking for the DataGridView.DataSource property. See http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridview.datasource(v=vs.90).aspx
For example:
//Set up the DataGridView either via code behind or the designer
DataGridView dgView = new DataGridView();
//You should turn off auto generation of columns unless you want all columns of
//your bound objects to generate columns in the grid
dgView.AutoGenerateColumns = false;
//Either in the code behind or via the designer you will need to set up the data
//binding for the columns using the DataGridViewColumn.DataPropertyName property.
DataGridViewColumn column = new DataGridViewColumn();
column.DataPropertyName = "PropertyName"; //Where you are binding Foo.PropertyName
dgView.Columns.Add(column);
//You can bind a List<Foo> as well, but if you later add new Foos to the list
//reference they won't be updated in the grid. If you use a binding list, they
//will be.
BindingList<Foo> listOfFoos = Repository.GetFoos();
dgView.DataSource = listOfFoos;
A handy event to bind to at that point is the DataGridView.DataBindingComplete which fires after the data source is bound.