DBProviderInfo.SupportsNullColumns 属性
Returns a Boolean that indicates if the table supports nullnull 引用（在 Visual Basic 中为 Nothing） columns. This field is read-only.
命名空间： Microsoft.SqlServer.Dts.Runtime
程序集： Microsoft.SqlServer.ManagedDTS（在 Microsoft.SqlServer.ManagedDTS.dll 中）
语法
声明
Public ReadOnly Property SupportsNullColumns As Boolean
Get
用法
Dim instance As DBProviderInfo
Dim value As Boolean
value = instance.SupportsNullColumns
public bool SupportsNullColumns { get; }
public:
property bool SupportsNullColumns {
bool get ();
}
member SupportsNullColumns : bool
function get SupportsNullColumns () : boolean
属性值
类型：System.Boolean
A Boolean that indicates if the table supports nullnull 引用（在 Visual Basic 中为 Nothing） columns. A value of true indicates that nullnull 引用（在 Visual Basic 中为 Nothing） columns are supported.
示例
The following example enumerates the properties of the database providers available on the computer.
namespace dbproviderinfo
{
class Program
{
static void Main(string[] args)
{
Application app = new Application();
DBProviderInfos dbis = app.DBProviderInfos;
foreach (DBProviderInfo dbi in dbis)
{
Console.WriteLine("Description = {0}, Name = {1}, ParseName = {2}", dbi.Description, dbi.Name, dbi.ParseName);
Console.WriteLine("ProviderSubType ={0}, ProviderType = {1}", dbi.ProviderSubType, dbi.ProviderType);
Console.WriteLine("SupportsNullColumns = {0}, UseFullTableName = {1}", dbi.SupportsNullColumns, dbi.UseFullTableName);
}
}
}
}
Namespace dbproviderinfo
Class Program
Shared Sub Main(ByVal args() As String)
Dim app As Application = New Application()
Dim dbis As DBProviderInfos = app.DBProviderInfos
Dim dbi As DBProviderInfo
For Each dbi In dbis
Console.WriteLine("Description = {0}, Name = {1}, ParseName = {2}", dbi.Description, dbi.Name, dbi.ParseName)
Console.WriteLine("ProviderSubType ={0}, ProviderType = {1}", dbi.ProviderSubType, dbi.ProviderType)
Console.WriteLine("SupportsNullColumns = {0}, UseFullTableName = {1}", dbi.SupportsNullColumns, dbi.UseFullTableName)
Next
End Sub
End Class
End Namespace
Sample output:
Description = MediaCatalogDB OLE DB Provider, Name = MediaCatalogDB OLE DB Provider, ParseName = {09E767A6-4481-4791-86A5-A739E5290E4C}
ProviderSubType =None, ProviderType = OleDb
SupportsNullColumns = True, UseFullTableName = True
Description = Microsoft OLE DB Provider for SQL Server, Name = SQLOLEDB, ParseName = {0C7FF16C-38E3-11d0-97AB-00C04FC2AD98}
ProviderSubType =SqlServer, ProviderType = OleDb
SupportsNullColumns = True, UseFullTableName = True