public class TestClass
    {
     public Form MyForm = new Form();

     public TestClass()
          {
           _GenerateForm(string "wwweee");

           }
     
     private void _GenerateForm(string ElementName)
          {
          TextBox element = new TextBox();
            element.Text = "qweasd";
            element.MaxLength = 10;
            element.Name = ElementName;
           
            element.parent = MyForm ;
            
            Button btOk = new Button();
            btOk.Text = "ОК";
            btOk.Parent = MyForm ;
            btOk.Left = 100;
            btOk.Top = 100;
            btOk.Click += new EventHandler(onForm_BtOkClick);
           }
        void onForm_BtOkClick(object sender, EventArgs e)
        {
             /* 
                  как тут получить значение 
                  textBox ???
            */

             string result = "";
			foreach (Control mayBeTextBox in this.Controls)
			{
				if (mayBeTextBox.Name == "wwweee")
				{
					result = mayBeTextBox.Text;
				}
			}


             MasterForm.DialogResult = DialogResult.OK;
        }
       public DialogResult ShowDialog()
        {
            /* 
                  так же если тоже.
            */
 
            return this.MyForm.ShowDialog();
        }
     }