IDataParameter.IsNullable Property
Definition
Important
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Gets a value indicating whether the parameter accepts null values.
public:
property bool IsNullable { bool get(); };
public bool IsNullable { get; }
member this.IsNullable : bool
Public ReadOnly Property IsNullable As Boolean
Property Value
true
if null values are accepted; otherwise, false
. The default is false
.
Examples
The following example creates an instance of the implementing class, SqlParameter, and sets some of its properties.
private static void AddSqlParameter(SqlCommand command,
string paramValue)
{
SqlParameter parameter = new SqlParameter(
"@Description", SqlDbType.VarChar);
parameter.Value = paramValue;
parameter.IsNullable = true;
command.Parameters.Add(parameter);
}
private static void SetParameterToNull(IDataParameter parameter)
{
if (parameter.IsNullable)
{
parameter.Value = DBNull.Value;
}
else
{
throw new ArgumentException("Parameter provided is not nullable", "parameter");
}
}
Private Sub AddSqlParameter(ByVal command As SqlCommand, _
ByVal paramValue As String)
Dim parameter As New SqlParameter( _
"@Description", SqlDbType.NVarChar, 16)
parameter.Value = paramValue
parameter.IsNullable = True
command.Parameters.Add(parameter)
End Sub
Private Shared Sub SetParameterToNull(parameter As IDataParameter)
If parameter.IsNullable Then
parameter.Value = DBNull.Value
Else
Throw New ArgumentException("Parameter provided is not nullable", "parameter")
End If
End Sub
Remarks
Null values are handled using the DBNull class.
Applies to
Met ons samenwerken op GitHub
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