DataBinding.Expression 속성

정의

네임스페이스:

System.Web.UI

어셈블리:

System.Web.dll

계산될 데이터 바인딩 식을 가져오거나 설정합니다.

public:
 property System::String ^ Expression { System::String ^ get(); void set(System::String ^ value); };

public string Expression { get; set; }

member this.Expression : string with get, set

Public Property Expression As String

속성 값

String

계산될 데이터 바인딩 식입니다.

예제

다음 코드 예제에서는 DataBinding 개체 및 컨트롤의 기존 개체 같음 집합 DataBindingCollection 포함 된 컬렉션을 propertyName 매개 변수 값을 사용 하 여 Text입니다. 컬렉션에 포함 하는 경우는 DataBinding 개체를 propertyName 의 값 Text,이 코드는 개체의 값을 반환 합니다. Expression 속성. 이러한 개체가 없으면 빈 문자열 반환 합니다 ("").

// 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