DataBinding(String, Type, String) Constructor

Definition

Namespace:

System.Web.UI

Assembly:

System.Web.dll

Initializes a new instance of the DataBinding class.

public:
 DataBinding(System::String ^ propertyName, Type ^ propertyType, System::String ^ expression);

public DataBinding (string propertyName, Type propertyType, string expression);

new System.Web.UI.DataBinding : string * Type * string -> System.Web.UI.DataBinding

Public Sub New (propertyName As String, propertyType As Type, expression As String)

Parameters

propertyName

String

The property to bind data to.

propertyType

Type

The .NET Framework type of the property to bind data to.

expression

String

The data-binding expression to be evaluated.

Examples

The following code example creates a DataBinding object and sets it equal to an existing object in the control's DataBindingCollection collection that has a propertyName parameter with a value of Text. If the collection contains a DataBinding object with a propertyName value of Text, this code returns the value of the object's Expression property. If there is no such object, it returns an empty string ("").

// Create a Text property with accessors that obtain 
// the property value from and set the property value
// to the Text key in the DataBindingCollection class.
public string Text
{
    get
    {
        DataBinding myBinding = DataBindings["Text"];
        if (myBinding != null)
        {
            return myBinding.Expression;
        }
        return String.Empty;
    }
    set
    {

        if ((value == null) || (value.Length == 0))
        {
            DataBindings.Remove("Text");
        }
        else
        {

            DataBinding binding = DataBindings["Text"];

            if (binding == null)
            {
                binding = new DataBinding("Text", typeof(string), value);
            }
            else
            {
                binding.Expression = value;
            }
            // Call the DataBinding constructor, then add
            // the initialized DataBinding object to the 
            // DataBindingCollection for this custom designer.
            DataBinding binding1 = (DataBinding)DataBindings.SyncRoot;
            DataBindings.Add(binding);
            DataBindings.Add(binding1);
        }
        PropertyChanged("Text");
    }
}

' Create a Text property with accessors that obtain 
' the property value from and set the property value
' to the Text key in the DataBindingCollection class.

Public Property [Text]() As String
    Get
        Dim myBinding As DataBinding = DataBindings("Text")
        If Not (myBinding Is Nothing) Then
            Return myBinding.Expression
        End If
        Return String.Empty
    End Get
    Set(ByVal value As String)

        If value Is Nothing OrElse value.Length = 0 Then
            DataBindings.Remove("Text")
        Else

            Dim binding As DataBinding = DataBindings("Text")

            If binding Is Nothing Then
                binding = New DataBinding("Text", GetType(String), value)
            Else
                binding.Expression = value
            End If
            ' Call the DataBinding constructor, then add
            ' the initialized DataBinding object to the 
            ' DataBindingCollection for this custom designer.
            Dim binding1 As DataBinding = CType(DataBindings.SyncRoot, DataBinding)
            DataBindings.Add(binding)
            DataBindings.Add(binding1)
        End If
        PropertyChanged("Text")
    End Set
End Property

See also

• DataBinder