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AllowNull Property

FarPoint.Win Assembly > FarPoint.Win Namespace > SuperEditBase Class : AllowNull Property
Gets or sets whether the control considers a null value valid.
Public Overridable Property AllowNull As Boolean
Dim instance As SuperEditBase
Dim value As Boolean
instance.AllowNull = value
value = instance.AllowNull
public virtual bool AllowNull {get; set;}

Property Value

Boolean value: true to allow null as user input; false otherwise

When this property is set to true, the edit control accepts null values, and the user can provide a null value in the following ways:

This property is available from the SuperEditBase class.

This property must be set to true for the NullColor property to work correctly.

You can return whether a control contains the null value by calling the IsNull method.

private void Form1_Load(object sender, System.EventArgs e)
   control.NullColor = Color.Coral;
   control.AllowNull = true;
   control.CausesValidation = true;
   control.Text = "";

private void button1_Click(object sender, System.EventArgs e)
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
   control.NullColor = Color.Coral
   control.AllowNull = True
   control.CausesValidation = True
   control.Text = ""
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
End Sub
See Also


SuperEditBase Class
SuperEditBase Members
NullColor Property
Text Property
SetNull Method
IsNull Method