• 项目

IsDBNull 方法

Returns a Boolean that contains a value indicating whether the column is set to null.

命名空间：  Microsoft.AnalysisServices.AdomdClient
程序集：  Microsoft.AnalysisServices.AdomdClient（在 Microsoft.AnalysisServices.AdomdClient.dll 中）

语法

声明
Public Function IsDBNull ( _
    ordinal As Integer _
) As Boolean
用法
Dim instance As AdomdDataReader
Dim ordinal As Integer
Dim returnValue As Boolean

returnValue = instance.IsDBNull(ordinal)

public bool IsDBNull(
    int ordinal
)

public:
virtual bool IsDBNull(
    int ordinal
) sealed

abstract IsDBNull : 
        ordinal:int -> bool 
override IsDBNull : 
        ordinal:int -> bool 

public final function IsDBNull(
    ordinal : int
) : boolean

参数

返回值

类型：System. . :: . .Boolean
A Boolean containing true if the column is set to nullNothingnullptrunitnull 引用（在 Visual Basic 中为 Nothing）; false otherwise.

实现

IDataRecord. . :: . .IsDBNull(Int32)

注释

Call this method to check for null Nothing nullptr unit null 引用（在 Visual Basic 中为 Nothing） column values before calling the typed methods used to retrieve column values (for example, GetByte, GetChar, and so on), to avoid raising an error.