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DataTypeInfoEnumerator.MoveNext Method

Definition

Advances the enumerator to the next element of the collection.

public:
 virtual bool MoveNext();
public bool MoveNext ();
abstract member MoveNext : unit -> bool
override this.MoveNext : unit -> bool
Public Function MoveNext () As Boolean

Returns

A Boolean that indicates if MoveNext() was successful. true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection

Implements

Examples

The following code example creates an enumerator, and then uses the Current, MoveNext, and Reset methods to navigate over the collection.

using System;  
using System.Collections.Generic;  
using System.Text;  
using Microsoft.SqlServer.Dts.Runtime;  

namespace DataTypeInfos_GetEnum_Current  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            //Create the DataTypeInfos collection.  
            DataTypeInfos dataInfos = new Application().DataTypeInfos;  

            //Create the enumerator.  
            DataTypeInfoEnumerator myEnumerator = dataInfos.GetEnumerator();  
            Console.WriteLine("The collection contains the following values:");  
            int i = 0;  
            DataTypeInfo dtiObject;  
            while ((myEnumerator.MoveNext()) && (myEnumerator.Current != null))  
            {  
                dtiObject = (DataTypeInfo)myEnumerator.Current;  
                Console.WriteLine("[{0}] {1} {2}", i++, dtiObject.TypeName, dtiObject.TypeEnumName);  
            }  
            // Reset puts the index pointer before the beginning  
           // of the collection.  
            // Do not retrieve from the collection until MoveNext is called.  
            myEnumerator.Reset();  
            myEnumerator.MoveNext();  

            // Now that the enumerator has been reset, and moved to the  
            // first item in the collection, show the first item.  
            dtiObject = (DataTypeInfo)myEnumerator.Current;  
            Console.WriteLine("The first item in the enumerator after Reset:");  
            Console.WriteLine("{0}, {1}", dtiObject.TypeName, dtiObject.TypeEnumName);  
        }  
    }  
}  
Imports System  
Imports System.Collections.Generic  
Imports System.Text  
Imports Microsoft.SqlServer.Dts.Runtime  

Namespace DataTypeInfos_GetEnum_Current  
    Class Program  
        Shared  Sub Main(ByVal args() As String)  
            'Create the DataTypeInfos collection.  
            Dim dataInfos As DataTypeInfos =  New Application().DataTypeInfos   

            'Create the enumerator.  
            Dim myEnumerator As DataTypeInfoEnumerator =  dataInfos.GetEnumerator()   
            Console.WriteLine("The collection contains the following values:")  
            Dim i As Integer =  0   
            Dim dtiObject As DataTypeInfo  
            While (myEnumerator.MoveNext()) &&(myEnumerator.Current <> Nothing)  
                dtiObject = CType(myEnumerator.Current, DataTypeInfo)  
                Console.WriteLine("[{0}] {1} {2}",i = Console.WriteLine("[{0}] {1} {2}",i + 1  
            End While  
            ' Reset puts the index pointer before the beginning  
           ' of the collection.  
            ' Do not retrieve from the collection until MoveNext is called.  
            myEnumerator.Reset()  
            myEnumerator.MoveNext()  

            ' Now that the enumerator has been reset, and moved to the  
            ' first item in the collection, show the first item.  
            dtiObject = CType(myEnumerator.Current, DataTypeInfo)  
            Console.WriteLine("The first item in the enumerator after Reset:")  
            Console.WriteLine("{0}, {1}", dtiObject.TypeName, dtiObject.TypeEnumName)  
        End Sub  
    End Class  
End Namespace  

Sample Output:

The collection contains the following values:

[0] float DT_R4

[1] double-precision float DT_R8

[2] currency DT_CY

[3] date DT_DATE

[4] Boolean DT_BOOL

[5] decimal DT_DECIMAL

[6] single-byte signed integer DT_I1

[7] single-byte unsigned integer DT_UI1

[8] two-byte signed integer DT_I2

[9] two-byte unsigned integer DT_UI2

[10] four-byte signed integer DT_I4

[11] four-byte unsigned integer DT_UI4

[12] eight-byte signed integer DT_I8

[13] eight-byte unsigned integer DT_UI8

[14] file timestamp DT_FILETIME

[15] unique identifier DT_GUID

[16] byte stream DT_BYTES

[17] string DT_STR

[18] Unicode string DT_WSTR

[19] numeric DT_NUMERIC

[20] database date DT_DBDATE

[21] database time DT_DBTIME

[22] database timestamp DT_DBTIMESTAMP

[23] image DT_IMAGE

[24] text stream DT_TEXT

[25] Unicode text stream DT_NTEXT

The first item in the enumerator after Reset:

float, DT_R4

Applies to