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DataRow.IsNull Method

Gets a value indicating whether the specified column contains a null value.

Overload List

Gets a value indicating whether the specified DataColumn contains a null value.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Function IsNull(DataColumn) As Boolean
[C#] public bool IsNull(DataColumn);
[C++] public: bool IsNull(DataColumn*);
[JScript] public function IsNull(DataColumn) : Boolean;

Gets a value indicating whether the column at the specified index contains a null value.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Function IsNull(Integer) As Boolean
[C#] public bool IsNull(int);
[C++] public: bool IsNull(int);
[JScript] public function IsNull(int) : Boolean;

Gets a value indicating whether the named column contains a null value.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Function IsNull(String) As Boolean
[C#] public bool IsNull(string);
[C++] public: bool IsNull(String*);
[JScript] public function IsNull(String) : Boolean;

Gets a value indicating whether the specified DataColumn and DataRowVersion contains a null value.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Function IsNull(DataColumn, DataRowVersion) As Boolean
[C#] public bool IsNull(DataColumn, DataRowVersion);
[C++] public: bool IsNull(DataColumn*, DataRowVersion);
[JScript] public function IsNull(DataColumn, DataRowVersion) : Boolean;

Example

[Visual Basic] The following example changes the value of a column to a null value, then uses the IsNull method to determine if the value is null.

[Visual Basic] Note   This example shows how to use one of the overloaded versions of IsNull. For other examples that might be available, see the individual overload topics.
[Visual Basic] 
Private Sub IsValNull()
   Dim t As DataTable
   Dim r As DataRow
   ' Assuming the DataGrid is bound to a DataTable.
   t = CType(DataGrid1.DataSource, DataTable)

   r = t.Rows(datagrid1.CurrentCell.RowNumber)
   r.BeginEdit
   r("FirstName") = System.DBNull.Value
   r.EndEdit
   r.AcceptChanges
   Console.WriteLine(r.IsNull("FirstName"))
End Sub

[C#, C++, JScript] No example is available for C#, C++, or JScript. To view a Visual Basic example, click the Language Filter button Language Filter in the upper-left corner of the page.

See Also

DataRow Class | DataRow Members | System.Data Namespace

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