动态创建窗体实例的三种方法

‘方法1 使用activator方法创建实例

        Dim str As String

        str = "Form2"  '必须是 命名空间+点+窗体类名（这里假设为命名空间为空）

        Dim tempAssembly As [Assembly] = [Assembly].GetExecutingAssembly()

        Dim t As Type = tempAssembly.GetType(str)

        Dim args() As Object = Nothing

        Dim o As Object = System.Activator.CreateInstance(t, args)

        CType(o, Form2).Show()

        'Dim frm2 As Form = CType(tempAssembly.CreateInstance(str), Form)

        'frm2.Show()

‘方法2 使用构造函数的invoke方法创建实例。

        Dim ty() As Type = {} ‘该构造函数没有参数

        Dim c As ConstructorInfo = t.GetConstructor(ty) ‘获得没有参数的构造函数

        Dim args1() As Object = Nothing ‘参数为空

        Dim p As Object = c.Invoke(Nothing) ‘创建实例时参数为空

        CType(p, Form2).Show()

‘方法3 ‘使用assembly.createinstance方法创建实例

        Dim str As String

        str = "Form2"  '必须是 命名空间+点+窗体类名

        Dim tempAssembly As System.Reflection.Assembly = System.Reflection.Assembly.GetExecutingAssembly()

        Dim frm2 As Form = CType(tempAssembly.CreateInstance(str), Form)

        frm2.Show()