Parameter.AllowNull Property

Specifies whether to treat an empty field as null.

Namespace: DevExpress.XtraReports.Parameters

Assembly: DevExpress.Printing.v25.1.Core.dll

NuGet Package: DevExpress.Printing.Core

Declaration

C#

[DefaultValue(false)]
public bool AllowNull { get; set; }

VB.NET

<DefaultValue(False)>
Public Property AllowNull As Boolean

Property Value

Type	Default	Description
Boolean	false	true, to treat an empty field as null; otherwise, treat an empty field as string.empty.

Remarks

The AllowNull option determines whether to treat an empty field as null or as string.empty (or as an empty array for the multi-value parameter).

C#

using DevExpress.XtraReports.Parameters;
// ...
report.Parameters["date"].AllowNull = true;

VB.NET

Imports DevExpress.XtraReports.Parameters
' ...
report.Parameters("date").AllowNull = True