求助：C++CLR form窗体应用程序中，如何限制textBox中光标始终在字符串最后。

private: System::Void textBox1_KeyPress(System::Object^ sender, System::Windows::Forms::KeyPressEventArgs^ e)
    {
        textBox2->Clear();
        if (e->KeyChar == 8) //退格键，不受限制。
            return;
        //if (e->KeyChar == '\\' || e->KeyChar == '/' || e->KeyChar == ':' || e->KeyChar == '*' || e->KeyChar == '?' || e->KeyChar == '"' || e->KeyChar == '<' || e->KeyChar == '>' || e->KeyChar == '|')
        //{
        //   
        //    textBox2->Text = "路径名不能包括下列任何字符\r\n\\ / : * ? \" < > |";
        //}            
        if (textBox1->Text == "")   //第-次输入硬盘分区，确认硬盘分区存在后，方可输入。。。。。
        {
            if (e->KeyChar >= 'C' && e->KeyChar <= 'Z' || e->KeyChar >= 'c' && e->KeyChar <= 'z')
            {
                char _disk_char[4] = {0,':','\\',0};
                _disk_char[0] = e->KeyChar >= 'C' && e->KeyChar <= 'Z' ? e->KeyChar :e->KeyChar - 32;
                String^ _disk = gcnew String(_disk_char);
                if (Directory::Exists(_disk))
                    textBox1->Text = _disk;
            }
            e->Handled = true;
            textBox1->Select(textBox1->Text->Length, 0);
        }
        else
        {
            if (e->KeyChar == ':' && textBox1->Text->Length != 1)
                e->Handled = true;
            else if (textBox1->Text->Length == 2 && e->KeyChar != '\\')
                e->Handled = true;
            else if (e->KeyChar == '\\' && textBox1->Text->EndsWith("\\"))
                e->Handled = true;
            else if (e->KeyChar == '/'|| e->KeyChar == '*' || e->KeyChar == '?' || e->KeyChar == '"' || e->KeyChar == '<' || e->KeyChar == '>' || e->KeyChar == '|')
                e->Handled = true;
        }

    }
private: System::Void button1_Click(System::Object^ sender, System::EventArgs^ e)
{
    textBox2->Clear();
    if (textBox1->Text == "")
    {
        textBox2->Text = "没有输入任何路径";
    }
    else
    {
        String^ path_name = nullptr;
        try
        {
            if (!Directory::Exists(textBox1->Text))
            {
                textBox2->Text = "开始创建 \"" + textBox1->Text + "\" 目录";
                DirectoryInfo^ credir = Directory::CreateDirectory(textBox1->Text);   
                path_name = credir->FullName;
            }
            else
            {
                textBox2->Text = textBox1->Text + "目录已经存在";
            }
        }
        catch (Exception^ e)
        {
            textBox2->Text +="\r\n目录创建失败\r\n"+ e->Message;
        }
        finally
        {
            if(path_name!=nullptr)
                textBox2->Text += "\r\n创建目录 \"" + path_name + "\"\r\n请确认是否正确";
        }
    }
}