StringCollection::Clear Method ()

 
System_CAPS_noteNote

The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

Removes all the strings from the StringCollection.

Namespace:   System.Collections.Specialized
Assembly:  System (in System.dll)

public:
virtual void Clear() sealed

Implements

IList::Clear()

Count is set to zero, and references to other objects from elements of the collection are also released.

This method is an O(n) operation, where n is Count.

The following code example removes elements from the StringCollection.

#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
void PrintValues( IEnumerable^ myCol );
int main()
{

   // Creates and initializes a new StringCollection.
   StringCollection^ myCol = gcnew StringCollection;
   array<String^>^myArr = {"RED","orange","yellow","RED","green","blue","RED","indigo","violet","RED"};
   myCol->AddRange( myArr );
   Console::WriteLine( "Initial contents of the StringCollection:" );
   PrintValues( myCol );

   // Removes one element from the StringCollection.
   myCol->Remove( "yellow" );
   Console::WriteLine( "After removing \"yellow\":" );
   PrintValues( myCol );

   // Removes all occurrences of a value from the StringCollection.
   int i = myCol->IndexOf( "RED" );
   while ( i > -1 )
   {
      myCol->RemoveAt( i );
      i = myCol->IndexOf( "RED" );
   }

   Console::WriteLine( "After removing all occurrences of \"RED\":" );
   PrintValues( myCol );

   // Clears the entire collection.
   myCol->Clear();
   Console::WriteLine( "After clearing the collection:" );
   PrintValues( myCol );
}

void PrintValues( IEnumerable^ myCol )
{
   IEnumerator^ myEnum = myCol->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "   {0}", obj );
   }

   Console::WriteLine();
}

/*
This code produces the following output.

Initial contents of the StringCollection:
   RED
   orange
   yellow
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing "yellow":
   RED
   orange
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing all occurrences of "RED":
   orange
   green
   blue
   indigo
   violet

After clearing the collection:

*/

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Return to top
Show: