模拟软键盘 点击软键盘TextBox中的光标总在最前面

Question

From的控件textBox1，pictureBox1,pictureBox2
代码如下         public Form1
        {
         .....
         this.pictureBox1.Click += new EventHandler(pictureBox_Click);
         this.pictureBox2.Click += new EventHandler(pictureBox_Click);
         }         private void pictureBox_Click(object sender, EventArgs e)
         {
            TextBox textBox = (TextBox)this.ActiveControl;
                if (textBox.Name.Equals("textBox1"))
                {
                    PictureBox picBox = (PictureBox)sender;
                    this.txtolNbr.Text += picBox.Name.Substring(picBox.Name.Length - 1, 1);
                }
         }为什么每次点击picBox后，textBox1中的光标总在最前端，而不是在最后面

Answer 1

TextBoxControl.SelectionStart = TextBoxControl.TextLength; 

Answer 2

TextBoxControl.SelectionStart = TextBoxControl.Text.Length; 

Answer 3

谢谢啦我还想问个问题 
现在textBox1中文本是"123"，我把光标移到"2"的后面,我点击picBoxBack(退格键)，如何让textBox1中的文本变为"13"

Answer 4

//在picBoxBack(退格键)事件中调用
SendKeys.Send("{BACKSPACE}");