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ColumnAttribute.CanBeNull Property

Gets or sets whether a column can contain null values.

Namespace:  System.Data.Linq.Mapping
Assembly:  System.Data.Linq (in System.Data.Linq.dll)

public bool CanBeNull { get; set; }

Property Value

Type: System.Boolean
Default = true.

If you set this value to false, the data in the corresponding column is assumed to be non-null.

NoteNote

This property is duplicated from the DbType property for convenience. The CreateDatabase method uses only the DbType property. For this reason, you must specify whether a column can contain null values in the DbType property also.


    [Column(Storage="_LastName", DbType="NVarChar(20) NOT NULL", CanBeNull=false)]
	public string LastName
	{
		get
		{
			return this._LastName;
		}
		set
		{
			if ((this._LastName != value))
			{
				this.OnLastNameChanging(value);
				this.SendPropertyChanging();
				this._LastName = value;
				this.SendPropertyChanged("LastName");
				this.OnLastNameChanged();
			}
		}
	}


.NET Framework

Supported in: 4, 3.5

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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