Why is windows form not working?

Question

.NET

Good day!
Why does the form event not work:

#pragma once

namespace RuslanTilyaev {

  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>
  /// Сводка для MyForm
  /// </summary>
  public ref class MyForm : public System::Windows::Forms::Form
  {
  public:
    MyForm(void)
    {
      InitializeComponent();
      //
      //TODO: добавьте код конструктора
      //
    }

  protected:
    /// <summary>
    /// Освободить все используемые ресурсы.
    /// </summary>
    ~MyForm()
    {
      if (components)
      {
        delete components;
      }
    }
  private: System::Windows::Forms::TextBox^ textBox1;
  private: System::Windows::Forms::TextBox^ textBox2;
  private: System::Windows::Forms::Button^ button1;
  private: System::Windows::Forms::TextBox^ textBox3;
  protected:

  private:
    /// <summary>
    /// Обязательная переменная конструктора.
    /// </summary>
    System::ComponentModel::Container ^components;

#pragma region Windows Form Designer generated code
    /// <summary>
    /// Требуемый метод для поддержки конструктора — не изменяйте 
    /// содержимое этого метода с помощью редактора кода.
    /// </summary>
    void InitializeComponent(void)
    {
      this->textBox1 = (gcnew System::Windows::Forms::TextBox());
      this->textBox2 = (gcnew System::Windows::Forms::TextBox());
      this->button1 = (gcnew System::Windows::Forms::Button());
      this->textBox3 = (gcnew System::Windows::Forms::TextBox());
      this->SuspendLayout();
      // 
      // textBox1
      // 
      this->textBox1->Location = System::Drawing::Point(13, 78);
      this->textBox1->Name = L"textBox1";
      this->textBox1->Size = System::Drawing::Size(100, 20);
      this->textBox1->TabIndex = 0;
      // 
      // textBox2
      // 
      this->textBox2->Location = System::Drawing::Point(160, 78);
      this->textBox2->Name = L"textBox2";
      this->textBox2->Size = System::Drawing::Size(100, 20);
      this->textBox2->TabIndex = 1;
      // 
      // button1
      // 
      this->button1->Location = System::Drawing::Point(106, 124);
      this->button1->Name = L"button1";
      this->button1->Size = System::Drawing::Size(75, 23);
      this->button1->TabIndex = 2;
      this->button1->Text = L"button1";
      this->button1->UseVisualStyleBackColor = true;
      // 
      // textBox3
      // 
      this->textBox3->Location = System::Drawing::Point(28, 179);
      this->textBox3->Name = L"textBox3";
      this->textBox3->Size = System::Drawing::Size(100, 20);
      this->textBox3->TabIndex = 3;
      // 
      // MyForm
      // 
      this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
      this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
      this->ClientSize = System::Drawing::Size(284, 261);
      this->Controls->Add(this->textBox3);
      this->Controls->Add(this->button1);
      this->Controls->Add(this->textBox2);
      this->Controls->Add(this->textBox1);
      this->Name = L"Лабараторная работа";
      this->Text = L"Лабараторная работа";
      this->ResumeLayout(false);
      this->PerformLayout();

    }
#pragma endregion
  private: System::Void button1_Click(System::Object^ sender, System::EventArgs^) {
    double a1, b1, res1;
    a1 = Convert::ToDouble(textBox1->Text);
    b1 = Convert::ToDouble(textBox2->Text);
    res1 = a1 + b1;
    textBox3->Text = Convert::ToString(res1);
  }
  };
}

Must add the value of the first field with the second and display the result in the third field.

Answer 1

Obviously, because there is no subscription to the click event of button1.
PS. Very strange choice of c++/cli dialect in the presence of c#. You shouldn't do that.