C＃在键入时突出显示文本框中的当前字符

Question

我在单击或关注文本框选择字符时编写了这段代码突出显示但是当我输入（编辑）突出显示时无法显示（文本框有默认文本）

        textBox1.GotFocus += textbox1_OnFocus;

    private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) && (e.KeyChar != '.'))
        {
            e.Handled = true;
        }

        // only allow one decimal point
        if ((e.KeyChar == '.') && ((sender as TextBox).Text.IndexOf('.') > -1))
        {
            e.Handled = true;
        }

        textBox1.SelectionStart = textBox1.SelectionStart;
        textBox1.SelectionLength = 1;

    }

     private void textbox1_OnFocus(object sender, EventArgs e)
    {
        textBox1.Focus();
        textBox1.SelectionStart = 0 ;
        textBox1.SelectionLength = 1;

    }

    private void textBox1_MouseClick(object sender, MouseEventArgs e)
    {
        listBox1.Items.Add(textBox1.SelectionStart);
        textBox1.SelectionStart = textBox1.SelectionStart;
        textBox1.SelectionLength = 1;
    }

我如何编辑我的代码以获得正确答案？

Answer 1

我写的这个很管用，但我认为这不是个好方法

        private void textBox1_KeyUp(object sender, KeyEventArgs e)
    {
        textBox1.SelectionStart = textBox1.SelectionStart;
        textBox1.SelectionLength = 1;
    }

C＃在键入时突出显示文本框中的当前字符

C# highlight current char in textbox while typing

c#

highlight

char