Variables.Contains 方法

Returns a Boolean that indicates whether the items in the collection can be accessed by using indexing without throwing an exception.

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 Function Contains ( _
    index As Object _
) As Boolean
用法
Dim instance As Variables 
Dim index As Object 
Dim returnValue As Boolean 

returnValue = instance.Contains(index)
public bool Contains(
    Object index
)
public:
bool Contains(
    Object^ index
)
member Contains : 
        index:Object -> bool
public function Contains(
    index : Object
) : boolean

参数

  • index
    类型:System.Object
    The name, ID, description, or index of the variable to locate in the collection.

返回值

类型:System.Boolean
A Boolean that indicates whether the collection can be accessed by using indexing. A value of true indicates that the collection can be accessed by using the syntax Variables[index].If the Contains method returns false, this property will throw an exception. In C#, this property is the indexer for the Variables class.

示例

The following code example adds a variable to the package. The code example uses various methods to locate the variable and print out its name, value, and namespace.

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

namespace Adding_Variables
{
    class Program
    {
        static void Main(string[] args)
        {
            Application app = new Application();
            Package pkg = app.LoadPackage(@"C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx", null);
            Variables pkgVars = pkg.Variables;
            Variable myVar = pkg.Variables.Add("myCustomVar", false, "User", "3");

            // Verify whether the variable is in the collection now.
            Boolean hasMyVar = pkg.Variables.Contains("myCustomVar");
            Console.WriteLine("The variable was found? {0}", hasMyVar);

            // Loop over the collection using the foreach keyword.
            foreach (Variable pkgVar in pkgVars)
            {
                // Print variables only from the User namespace.
                if (pkgVar.Namespace == "User")
                {
                Console.WriteLine("Variable: {0}, {1}", pkgVar.Name, pkgVar.Value.ToString());
                 }
            }
            Console.WriteLine("---------------------------");
            // Loop over the collection using the Enumerator. 
            VariableEnumerator myEnum = pkg.Variables.GetEnumerator();
            int i = 0;
            while ((myEnum.MoveNext()) && (myEnum.Current != null))
                // Again, show variables only from the User namespace.
                if (myEnum.Current.Namespace == "User")
                {                
                    Console.WriteLine("[{0}] {1}, {2}", i++, myEnum.Current.Name, myEnum.Current.Namespace);
                }

            myEnum.Reset();
            Console.WriteLine("---------------------------");

            //Using the Item method syntax of [x], obtain the
            // first entry in the collection.
            myVar = pkgVars[0];
            Console.WriteLine("The name and namespace of the first variable is: {0}, {1}", myVar.Name, myVar.Namespace);
            String nameOfFirstItem = pkgVars[0].Name;
            Console.WriteLine("The name of the first variable is: {0}", nameOfFirstItem);
            //}
        }
    }
}
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
 
Namespace Adding_Variables
    Class Program
        Shared  Sub Main(ByVal args() As String)
            Dim app As Application =  New Application() 
            Dim pkg As Package =  app.LoadPackage("C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx",Nothing) 
            Dim pkgVars As Variables =  pkg.Variables 
            Dim myVar As Variable =  pkg.Variables.Add("myCustomVar",False,"User","3") 
 
            ' Verify whether the variable is in the collection now.
            Dim hasMyVar As Boolean =  pkg.Variables.Contains("myCustomVar") 
            Console.WriteLine("The variable was found? {0}", hasMyVar)
 
            ' Loop over the collection using the foreach keyword.
            Dim pkgVar As Variable
            For Each pkgVar In pkgVars
                ' Print variables only from the User namespace.
                If pkgVar.Namespace = "User" Then
                Console.WriteLine("Variable: {0}, {1}", pkgVar.Name, pkgVar.Value.ToString())
                End If
            Next
            Console.WriteLine("---------------------------")
            ' Loop over the collection using the Enumerator. 
            Dim myEnum As VariableEnumerator =  pkg.Variables.GetEnumerator() 
            Dim i As Integer =  0 
            While (myEnum.MoveNext()) &&(myEnum.Current <> Nothing)
                    Console.WriteLine("[{0}] {1}, {2}",i = Console.WriteLine("[{0}] {1}, {2}",i + 1
            End While
 
            myEnum.Reset()
            Console.WriteLine("---------------------------")
 
            'Using the Item method syntax of [x], obtain the
            ' first entry in the collection.
            myVar = pkgVars(0)
            Console.WriteLine("The name and namespace of the first variable is: {0}, {1}", myVar.Name, myVar.Namespace)
            Dim nameOfFirstItem As String =  pkgVars(0).Name 
            Console.WriteLine("The name of the first variable is: {0}", nameOfFirstItem)
            '}
        End Sub
    End Class
End Namespace

Sample Output:

The variable was found? True

Variable: myCustomVar, 3

---------------------------

[0] myCustomVar, User

---------------------------

The name and namespace of the first variable is: CancelEvent, System

The name of the first variable is: CancelEvent

请参阅

参考

Variables 类

Microsoft.SqlServer.Dts.Runtime 命名空间