C# Tutorial - Binding a DataGridView to a Collection
This tutorial is kind of a follow-up to my previous tutorial about binding a DataGridView to an Access database. In this tutorial, I'm going to demonstrate how to bind a DataGridView to a .NET collection.
| Before we can build a collection of objects, we first need an object. I tend to use a Car object for most of my examples. The car object simply holds some information about a typical car - make, model, and year. Below is the object I'm going to use. |
{
private string _make;
private string _model;
private int _year;
public Car(string make, string model, int year)
{
_make = make;
_model = model;
_year = year;
}
public string Make
{
get { return _make; }
set { _make = value; }
}
public string Model
{
get { return _model; }
set { _model = value; }
}
public int Year
{
get { return _year; }
set { _year = value; }
}
}
All right, now that we've got an object, we need a collection to hold them. One of my favorite collection objects is the List, located in the System.Collections.Generic namespace, so we'll start with that.
cars.Add(new Car("Ford", "Mustang", 1967));
cars.Add(new Car("Shelby AC", "Cobra", 1965));
cars.Add(new Car("Chevrolet", "Corvette Sting Ray", 1965));
Binding this to a DataGridView is painfully easy. Simply set the DataSource property of the DataGridView to the List.
What will happen is that the DataGridView will automatically create columns for each property in the Car object, then create a row for each Car in the List. What we've created here is one-way binding. Any changes made by the user in the DataGridView will also take place in the List. If we want changes made to a Car to update the DataGridView, the Car object will have to implement the INotifyPropertyChanged interface.
{
private string _make;
private string _model;
private int _year;
public event PropertyChangedEventHandler PropertyChanged;
public Car(string make, string model, int year)
{
_make = make;
_model = model;
_year = year;
}
public string Make
{
get { return _make; }
set
{
_make = value;
this.NotifyPropertyChanged("Make");
}
}
public string Model
{
get { return _model; }
set
{
_model = value;
this.NotifyPropertyChanged("Model");
}
}
public int Year
{
get { return _year; }
set
{
_year = value;
this.NotifyPropertyChanged("Year");
}
}
private void NotifyPropertyChanged(string name)
{
if(PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
Unfortunately, this won't be enough. The List class does not support notifications from objects within its collection. Fortunately, there is an object that does - the BindingList. For the most part, the BindingList is used exactly like a List.
cars.Add(new Car("Ford", "Mustang", 1967));
cars.Add(new Car("Shelby AC", "Cobra", 1965));
cars.Add(new Car("Chevrolet", "Corvette Sting Ray", 1965));
_dgCars.DataSource = cars;
Now, if any external process, like a network thread, makes a change to a Car object, the DataGridView will automatically update to reflect the change.
Now we've got data in the DataGridView and any changes to the UI or the List will automatically update the other. Usually my properties aren't named something that are so user friendly. What happens when I want my columns named something else? This can be easily accomplished by disabling the AutoGenerateColumns property and by setting up the columns ourselves.
DataGridViewTextBoxColumn makeColumn = new DataGridViewTextBoxColumn();
makeColumn.DataPropertyName = "Make";
makeColumn.HeaderText = "The Car's Make";
DataGridViewTextBoxColumn modelColumn = new DataGridViewTextBoxColumn();
modelColumn.DataPropertyName = "Model";
modelColumn.HeaderText = "The Car's Model";
DataGridViewTextBoxColumn yearColumn = new DataGridViewTextBoxColumn();
yearColumn.DataPropertyName = "Year";
yearColumn.HeaderText = "The Car's Year";
_dgCars.Columns.Add(makeColumn);
_dgCars.Columns.Add(modelColumn);
_dgCars.Columns.Add(yearColumn);
BindingList<Car> cars = new BindingList<Car>();
cars.Add(new Car("Ford", "Mustang", 1967));
cars.Add(new Car("Shelby AC", "Cobra", 1965));
cars.Add(new Car("Chevrolet", "Corvette Sting Ray", 1965));
_dgCars.DataSource = cars;
Setting up the columns is pretty straight forward. There's all types of DataGridViewColumns, but I went with the basic TextBox version. All you have to do it set the HeaderText, which is what the user will see, and the DataPropertyName, which is the name of the property of the object that is bound to the DataGridView. Here's what our DataGridView looks like now:
I think that does it for binding a collection to a DataGridView. Data binding is a very powerful tool and we haven't even begun scratching the surface. If you have any questions leave us a comment.
Posted in C#, All Tutorials by The Reddest |
May 6th, 2008 at 10:44 am
Look forward to reading more about WinForm and binding, ‘beyond surface’.
Thanks
May 6th, 2008 at 5:24 pm
Thanks! That was very clear and helpfull!
May 19th, 2008 at 2:40 pm
Thanks for the info. Any way to enable the inserting of data?
May 19th, 2008 at 4:21 pm
You need to set the property AllowUserToAddRows to true. Any items added to the DataGridView will also be added to the collection bound to it (if you use a collection that supports two-way binding).
June 16th, 2008 at 4:44 am
Hello,
what if I’ve bound a list to the DataGridView in a multi-threaded application. How do I Invoke() in the automatic update of DataGridView in case of adding a new member to the list?
June 16th, 2008 at 7:46 am
@Sindik
That is not something I’ve found a clean solution to yet. At this point, I usually expose a control that can be used for the invoke. Either the actual DataGridView or the application’s main form. Then, you’ll want to invoke a function that actually adds to the list using the exposed control. That way, the automatic update is also done in the invoked code.
June 25th, 2008 at 2:01 am
I have created DataGridView and bind it with DataSource.
When I edit a single cell Value, and alos remain in that row, the dataset didn’t get Changes.
July 8th, 2008 at 6:48 am
Hi
Supose we have another class called Driver with Name and Age properties. Each car has only 1 driver and the class Car has a Driver property.
How to bind a column to the
Car.Driver.Name property ??
Thanks
July 14th, 2008 at 9:19 am
Exactly what I need, thanks a lot !
August 6th, 2008 at 6:17 am
Thanks. Just what I was after!
September 15th, 2008 at 2:45 pm
Thanks! very helpfull for beginners like myself