// Creates an empty CodeParameterDeclarationExpressionCollection.
CodeParameterDeclarationExpressionCollection collection = new CodeParameterDeclarationExpressionCollection();

// Adds a CodeParameterDeclarationExpression to the collection.
collection.Add( new CodeParameterDeclarationExpression(typeof(int), "testIntArgument") );

// Adds an array of CodeParameterDeclarationExpression objects 
// to the collection.
CodeParameterDeclarationExpression[] parameters = { new CodeParameterDeclarationExpression(typeof(int), "testIntArgument"), new CodeParameterDeclarationExpression(typeof(bool), "testBoolArgument") };
collection.AddRange( parameters );

// Adds a collection of CodeParameterDeclarationExpression objects 
// to the collection.
CodeParameterDeclarationExpressionCollection parametersCollection = new CodeParameterDeclarationExpressionCollection();
parametersCollection.Add( new CodeParameterDeclarationExpression(typeof(int), "testIntArgument") );
parametersCollection.Add( new CodeParameterDeclarationExpression(typeof(bool), "testBoolArgument") );
collection.AddRange( parametersCollection );

// Tests for the presence of a CodeParameterDeclarationExpression 
// in the collection, and retrieves its index if it is found.
CodeParameterDeclarationExpression testParameter = new CodeParameterDeclarationExpression(typeof(int), "testIntArgument");
int itemIndex = -1;
if( collection.Contains( testParameter ) )
    itemIndex = collection.IndexOf( testParameter );

// Copies the contents of the collection beginning at index 0 to the specified CodeParameterDeclarationExpression array.
// 'parameters' is a CodeParameterDeclarationExpression array.
collection.CopyTo( parameters, 0 );

// Retrieves the count of the items in the collection.
int collectionCount = collection.Count;

// Inserts a CodeParameterDeclarationExpression at index 0 
// of the collection.
collection.Insert( 0, new CodeParameterDeclarationExpression(typeof(int), "testIntArgument") );

// Removes the specified CodeParameterDeclarationExpression 
// from the collection.
CodeParameterDeclarationExpression parameter = new CodeParameterDeclarationExpression(typeof(int), "testIntArgument");
collection.Remove( parameter );

// Removes the CodeParameterDeclarationExpression at index 0.
collection.RemoveAt(0);