hey any one can tell me how to change the value of any control say a comboBox in a win32 forms project from the source cpp file as the form is created in a .h file and control is added in the .h file and i want to write the code in .cpp file and acces control from cpp file can anyone tell me how.actually i am new to vc++ gui programming ..

Code:
#pragma once


namespace diskinfo {

	using namespace System;
	using namespace System::ComponentModel;
	using namespace System::Collections;
	using namespace System::Windows::Forms;
	using namespace System::Data;
	using namespace System::Drawing;

	/// <summary>
	/// Summary for Form1
	///
	/// WARNING: If you change the name of this class, you will need to change the
	///          'Resource File Name' property for the managed resource compiler tool
	///          associated with all .resx files this class depends on.  Otherwise,
	///          the designers will not be able to interact properly with localized
	///          resources associated with this form.
	/// </summary>
	public ref class Form1 : public System::Windows::Forms::Form
	{
	public:
		Form1(void)
		{
			InitializeComponent();
			//
			//TODO: Add the constructor code here
			//
		}

	protected:
		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		~Form1()
		{
			if (components)
			{
				delete components;
			}
		}
	public: System::Windows::Forms::ComboBox^  comboBox1;
	protected: 

	private:
		/// <summary>
		/// Required designer variable.
		/// </summary>
		System::ComponentModel::Container ^components;

#pragma region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		void InitializeComponent(void)
		{
			this->comboBox1 = (gcnew System::Windows::Forms::ComboBox());
			this->SuspendLayout();
			// 
			// comboBox1
			// 
			this->comboBox1->FormattingEnabled = true;
			this->comboBox1->Location = System::Drawing::Point(79, 52);
			this->comboBox1->Name = L"comboBox1";
			this->comboBox1->Size = System::Drawing::Size(121, 21);
			this->comboBox1->TabIndex = 0;
			this->comboBox1->SelectedIndexChanged += gcnew System::EventHandler(this, &Form1::comboBox1_SelectedIndexChanged);
			// 
			// Form1
			// 
			this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
			this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
			this->ClientSize = System::Drawing::Size(292, 266);
			this->Controls->Add(this->comboBox1);
			this->Name = L"Form1";
			this->Text = L"Form1";
			this->ResumeLayout(false);

		}
#pragma endregion
	
	private: System::Void comboBox1_SelectedIndexChanged(System::Object^  sender, System::EventArgs^  e) {
			 }
	};
}

this is the .h file i had created of the form it has a combo box added i just want is to hcange or acces this control from the cpp file shown next


Code:

// diskinfo.cpp : main project file.

#include "stdafx.h"
#include "Form1.h"
#include"windows.h"
#include"stdio.h"
using namespace diskinfo;
#define BUFSIZE 512
[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
	char szTemp[512];
	//szTemp[0] = '\0';
	::GetLogicalDriveStringsA(BUFSIZE-1,szTemp);


	char *pch = szTemp;
while (*pch) {
printf("%s\n", pch);
pch = &pch[strlen(pch) + 1];
}
	
	

   ::Form1.comboBox1.Visible=false; this is where iam trying to access the combobox

	
	// Enabling Windows XP visual effects before any controls are created
	Application::EnableVisualStyles();
	Application::SetCompatibleTextRenderingDefault(false); 

	// Create the main window and run it
	Application::Run(gcnew Form1());
	return 0;



}