Introduction
We have already seen how to validate input data using DataAnnotations and DataInput controls. In this article we will see how it can be implemented to a DataGrid. That means validating user input in DataGrid.
Creating Silverlight ProjectFire up Visual Studio 2008 and create a Silverlight Application. Name it as DataValidationDataGridSL3.
Now we need a DataGrid to display sample data.
Go ahead and add it and name it as MyDataGrid.
Now we need to add a class which contains the properties of the sample data.
public class Users
{
public string Name { get; set; }
public int Age { get; set; }
public string Gender { get; set; }
public string Country { get; set; }
}DataAnnotation provides a developer friendly DataValidation techniques. So we need to add the assembly.
The ValidationException (belonging to System.ComponentModel.DataAnnotations ) thrown is displayed as Cell Validation Error.
Now that you have added the above assembly, use it in the Users.cs class and define the properties as required. As follows:
public class Users: INotifyPropertyChanged
{
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
#endregion
#region UserName
private string _UserName;
public string UserName
{
get { return _UserName; }
set
{
if (value.Length < 4)
{
throw new ValidationException("User Name should contain atleast 4 chars");
}
_UserName = value;
RaisePropertyChanged("UserName");
}
}
#endregion
#region Age
private int _Age;
public int Age
{
get { return _Age; }
set
{
_Age = value;
}
}
#endregion
#region Gender
private string _Gender;
public string Gender
{
get { return _Gender; }
set
{
_Gender = value;
}
}
#endregion
#region Country
private string _Country;
public string Country
{
get { return _Country; }
set
{
_Country = value;
}
}
#endregion
private void RaisePropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}Now add some sample data in the MainPage constructor and bind the DataGrid's ItemSource to the sample data.
public MainPage()
{
InitializeComponent();
List<Users> myList = new List<Users>
{
new Users{ UserName="Hiro Nakamura", Age=24, Gender="M", Country="Japan"},
new Users{ UserName="Mohinder Suresh", Age=26, Gender="M", Country="India"},
new Users{ UserName="Claire Bennette", Age=20, Gender="F", Country="USA"},
new Users{ UserName="Matt Parkman", Age=30, Gender="M", Country="USA"},
new Users{ UserName="Nathan Patrelli", Age=30, Gender="M", Country="USA"},
new Users{ UserName="Peter Patrelli", Age=26, Gender="M", Country="USA"},
new Users{ UserName="Mica Sanders", Age=19, Gender="M", Country="USA"},
new Users{ UserName="Linderman", Age=56, Gender="M", Country="USA"},
new Users{ UserName="Ando", Age=24, Gender="M", Country="Japan"},
new Users{ UserName="Maya", Age=24, Gender="F", Country="Mexico"},
new Users{ UserName="Angela Patrelli", Age=26, Gender="F", Country="USA"},
new Users{ UserName="Niki Sanders", Age=26, Gender="F", Country="USA"},
};
MyDataGrid.ItemsSource = myList;
}That's it run your application and try to change the first name and keep it empty or enter less than 4 characters. It will throw you a ValidationException. As follows:
Try for other columns as required.
Enjoy Coding.