DataColumnMappingCollection.Contains Method

Definition

Namespace:

System.Data.Common

Assembly:

System.Data.Common.dll

Gets a value indicating whether a DataColumnMapping object exists in the collection.

Overloads

Contains(Object)	Gets a value indicating whether a DataColumnMapping object with the given Object exists in the collection.
Contains(String)	Gets a value indicating whether a DataColumnMapping object with the given source column name exists in the collection.

Contains(Object)

Source:

DataColumnMappingCollection.cs

Gets a value indicating whether a DataColumnMapping object with the given Object exists in the collection.

public:
 virtual bool Contains(System::Object ^ value);

public bool Contains (object? value);

abstract member Contains : obj -> bool
override this.Contains : obj -> bool

Public Function Contains (value As Object) As Boolean

Parameters

value

Object

An Object that is the DataColumnMapping.

Returns

Boolean

true if the collection contains the specified DataColumnMapping object; otherwise, false.

Implements

Contains(Object)

Exceptions

InvalidCastException

The object passed in was not a DataColumnMapping object.

Examples

The following example searches for a DataColumnMapping within the collection. If the mapping exists in the collection, it is removed. If the mapping does not exist within the collection, it is added to the collection and its index is displayed. The example assumes that a DataColumnMappingCollection collection and a DataColumnMapping object have been created.

public void ChangedMyMind()
{
    // ...
    // create mappings and mapping
    // ...
    if (mappings.Contains((Object) mapping))
    {
        mappings.Remove((Object) mapping);
    }
    else
    {
        mappings.Add((Object) mapping);
        Console.WriteLine("Index of new mapping: " +
            mappings.IndexOf((Object) mapping));
    }
}

Public Sub ChangedMyMind()
    ' ...
    ' create mappings and mapping
    ' ...
    If mappings.Contains(CType(mapping, Object)) Then
        mappings.Remove(CType(mapping, Object))
    Else
        mappings.Add(CType(mapping, Object))
        Console.WriteLine("Index of new mapping: " & _
           mappings.IndexOf(CType(mapping, Object)).ToString())
    End If
End Sub

See also

• ADO.NET Overview

Contains(String)

Source:

DataColumnMappingCollection.cs

Gets a value indicating whether a DataColumnMapping object with the given source column name exists in the collection.

public:
 virtual bool Contains(System::String ^ value);

public bool Contains (string? value);

abstract member Contains : string -> bool
override this.Contains : string -> bool

Public Function Contains (value As String) As Boolean

Parameters

value

String

The case-sensitive source column name of the DataColumnMapping object.

Returns

Boolean

true if collection contains a DataColumnMapping object with the specified source column name; otherwise, false.

Implements

Contains(String)

Examples

The following example searches for a DataColumnMapping object with the given source column name within a DataColumnMappingCollection collection. If the DataColumnMapping exists, the example displays the name and the index of the mapping. If the mapping does not exist, the example displays an error. This example assumes that a DataColumnMappingCollection collection has been created.

public void FindDataColumnMapping()
{
    // ...
    // create columnMappings
    // ...
    if (!columnMappings.Contains("Description"))
    {
        Console.WriteLine("Error: no such table in collection.");
    }
    else
    {
        Console.WriteLine("Name {0}",
            columnMappings["Description"].ToString());
        Console.WriteLine("Index: {0}",
            columnMappings.IndexOf("Description").ToString());
    }
}

Public Sub FindDataColumnMapping()
    ' ...
    ' create columnMappings
    ' ...
    If Not columnMappings.Contains("Description") Then
        Console.WriteLine("Error: no such table in collection.")
    Else
       Console.WriteLine("Name: {0}", _
           columnMappings("Description").ToString())
       Console.WriteLine("Index: {0}", _
           columnMappings.IndexOf("Description").ToString())
    End If
End Sub

See also

• ADO.NET Overview