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DataReader.IsNullItem Method

Indicates whether the data item at the specified index is unspecified, that is, nulla null reference (Nothing in Visual Basic).

Namespace:  Microsoft.VisualStudio.Data
Assembly:  Microsoft.VisualStudio.Data (in Microsoft.VisualStudio.Data.dll)

Syntax

'Declaration
Public MustOverride Function IsNullItem ( _
    index As Integer _
) As Boolean
public abstract bool IsNullItem(
    int index
)
public:
virtual bool IsNullItem(
    int index
) abstract
abstract IsNullItem : 
        index:int -> bool 
public abstract function IsNullItem(
    index : int
) : boolean

Parameters

  • index
    Type: System.Int32
    Index of the data item to examine.

Return Value

Type: System.Boolean
Returns true if the item is nulla null reference (Nothing in Visual Basic), that is, unspecified; otherwise returns false.

Exceptions

Exception Condition
ArgumentOutOfRangeException

The index parameter is invalid.

Remarks

Calling this method to figure out if a value is nulla null reference (Nothing in Visual Basic) performs better than retrieving the value to see if it is equal to Value, because the latter causes the entire value to be read from the data reader instance.

.NET Framework Security

See Also

Reference

DataReader Class

Microsoft.VisualStudio.Data Namespace

DBNull