你能创建用于更改文本框的switch语句吗？ [英] Can you create switch statements for changing text boxes?

问题描述

嗨


我正在尝试创建一个程序，单击确定按钮将移动到下一个文本框。我认为我可以使用if语句和第一个if语句来实现这一点，但是当添加第二个和第三个if语句时解决方案崩溃了。



我需要的是一种模仿休息的方法。在switch语句中或更好地将我的if转换为switch。我试图这样做，但我不知道我应该在开关支架中添加什么变量，因为Textbox是一种类型，因此在我需要的上下文中无效。



如果有人对如何纠正或解决这个问题有任何想法，我将非常感谢您提供的任何帮助。



谢谢。



我的尝试：



当前代码：

Hi
I am trying to create a program that when the OK button is clicked will move onto the next text box. I thought I could do this using if statements and the first if statement worked however, when adding the second and third if statements the solution fell apart.

What I need is a way to emulate "break;" in a switch statement or better yet convert my "if's" into "switches". I have attempted to do so, but I don't know what variable I should be putting in the switch bracket since "Textbox" is a type and so not valid in the context I require.

If anyone has any ideas on how I could correct this or work around it I would be grateful for any help you could offer.

Thank you.

What I have tried:

current code:

private void btn_OK_Click(object sender, EventArgs e)
        {
            if (txt_Hours.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = true;
                txt_Seconds.Enabled = false;
            } 
                                   
            if (txt_Minutes.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = false;
                txt_Seconds.Enabled = true;
            }

            if (txt_Seconds.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = false;
                txt_Seconds.Enabled = false;
            }

尝试代码：

attempted code:

private void btn_OK_Click(object sender, EventArgs e)
        {
            switch (TextBox)
            {
                case txt_Hours.Enabled == true:
                    txt_Hours.Enabled = false;
                    txt_Minutes.Enabled = true;
                    txt_Seconds.Enabled = false;
                    break;

                case txt_Minutes.Enabled = true:
                    txt_Hours.Enabled = false;
                    txt_Minutes.Enabled = false;
                    txt_Seconds.Enabled = true;
                    break;

                case txt_Seconds.Enabled = true:
                    txt_Hours.Enabled = false;
                    txt_Minutes.Enabled = false;
                    txt_Seconds.Enabled = false;
                    break;
            } 

推荐答案

首先考虑一下你想做什么。这不起作用：

Start by thinking about what you want to do. This won't work:

if (txt_Hours.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = true;
                txt_Seconds.Enabled = false;
            } 
            if (txt_Minutes.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = false;
                txt_Seconds.Enabled = true;
            }
            if (txt_Seconds.Enabled == true)
            {
                txt_Hours.Enabled = false;
                txt_Minutes.Enabled = false;
                txt_Seconds.Enabled = false;
            }

因为如果第一种情况通过，它会设置一个条件，使第二种情况通过（通过启用txt_Minutes），它设置一个使第三种情况通过的条件 - 所以无论哪一种条件它开始，它总是结束相同：所有禁用。



你可以做到这一点，否则条件：

Because if the first case passes, it sets a condition which makes the second case pass (by enabling txt_Minutes), which sets a condition which makes the third case pass - so regardless of which condition it start in, it always ends up teh same: All disabled.

You can do it, with else conditions:

if (txt_Hours.Enabled == true)
{
    txt_Hours.Enabled = false;
    txt_Minutes.Enabled = true;
    txt_Seconds.Enabled = false;
}
else if (txt_Minutes.Enabled == true)
{
    txt_Hours.Enabled = false;
    txt_Minutes.Enabled = false;
    txt_Seconds.Enabled = true;
}
else if (txt_Seconds.Enabled == true)
{
    txt_Hours.Enabled = false;
    txt_Minutes.Enabled = false;
    txt_Seconds.Enabled = false;
}
else
{
    // Dunno what you want to do here...
}

但是你可以使用开关可以轻松实现，因为switch表达式只能用于sbyte，byte，short，ushort，int，uint，long，ulong，char，string或enum值和case语句仅适用于常量值。

But you can't do that easily with a switch because switch expressions only ever work with sbyte, byte, short, ushort, int, uint, long, ulong, char, string, or enum values, and case statements only work with constant values.

这篇关于你能创建用于更改文本框的switch语句吗？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！