Question

我是C＃的新手。我正在学习像ms windows计算器那样制作一个计算器。当我点击它时按钮工作，但我希望小键盘也可以工作。假设用户键入'0'，它应该与他点击我的gui上的0按钮相同。这是我的按钮点击事件0。

private void button0_Click(object sender, EventArgs e)
        {
            checkifequa();
            textBox1.Text = textBox1.Text + "0";
        }

如何让keydown工作？

修改

这是完整的来源。它是由youtube上的某个人所改变的，我只是修改并试图学习。请指出任何错误并提出更好的方法。



using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        bool plus = false;
        bool minus = false;
        bool into = false;
        bool divd = false;
        bool equa = false;
        public Form1()
        {
            InitializeComponent();
        }

    private void button0_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "0";
    }

    private void button1_Click(object sender, EventArgs e)
    {
        checkifequa();

        textBox1.Text = textBox1.Text + "1";
    }

    private void checkifequa()
    {
        if (equa)
            textBox1.Text = "";
        equa = false;
    }

    private void button2_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "2";
    }

    private void button3_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "3";
    }

    private void button4_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "4";
    }

    private void button5_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "5";
    }

    private void button6_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "6";
    }

    private void button7_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "7";
    }

    private void button8_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "8";
    }

    private void button9_Click(object sender, EventArgs e)
    {
        checkifequa();
        textBox1.Text = textBox1.Text + "9";
    }

    private void button11_Click(object sender, EventArgs e)
    {
        checkifequa();
        if(textBox1.Text.Contains("."))
        {
            return;
        }
        else
        {
        textBox1.Text=textBox1.Text+".";
        }

    }

    private void plusminus_Click(object sender, EventArgs e)
    {
        if (textBox1.Text.Contains("-"))
        {
            textBox1.Text = textBox1.Text.Remove(0, 1);
        }
        else
        {
            textBox1.Text = "-" + textBox1.Text;
        }
    }

    private void plus_Click(object sender, EventArgs e)
    {
        if (textBox1.Text == "")
        {
            return;
        }
        else
        { 
            plus = true;
            textBox1.Tag = textBox1.Text;
            textBox1.Text = "";
        }

    }

    private void equal_Click(object sender, EventArgs e)
    {
        equa = true;

        if (plus)
        {
            decimal dec = Convert.ToDecimal(textBox1.Tag) + Convert.ToDecimal(textBox1.Text);
            textBox1.Text = dec.ToString();

        }
        if (minus)
        {
            decimal dec = Convert.ToDecimal(textBox1.Tag) - Convert.ToDecimal(textBox1.Text);
            textBox1.Text = dec.ToString();

        }
        if (into)
        {
            decimal dec = Convert.ToDecimal(textBox1.Tag) * Convert.ToDecimal(textBox1.Text);
            textBox1.Text = dec.ToString();

        }
        if (divd)
        {
            decimal dec = Convert.ToDecimal(textBox1.Tag) / Convert.ToDecimal(textBox1.Text);
            textBox1.Text = dec.ToString();

        }
    }

    private void substract_Click(object sender, EventArgs e)
    {

        if (minus)
            if (textBox1.Text == "")
            {
                return;
            }
            else
            {
                minus = true;
                textBox1.Tag = textBox1.Text;
                textBox1.Text = "";
            }
    }

    private void multiply_Click(object sender, EventArgs e)
    {
        if (textBox1.Text == "")
        {
            return;
        }
        else
        {
            into = true;
            textBox1.Tag = textBox1.Text;
            textBox1.Text = "";
        }
    }

    private void divide_Click(object sender, EventArgs e)
    {
        if (textBox1.Text == "")
        {
            return;
        }
        else
        {
            divd = true;
            textBox1.Tag = textBox1.Text;
            textBox1.Text = "";
        }
    }

    private void clear_Click(object sender, EventArgs e)
    {
        plus = minus = into = divd = equa = false;
        textBox1.Text = "";
        textBox1.Tag = "";

    }




    void Form1_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (e.KeyChar >= 48 && e.KeyChar <= 57)
        {
            switch (e.KeyChar)
            {
                case (char)48:
                    button0.PerformClick();
                    break;

                case (char)49:
                    button1.PerformClick();
                    break;
                case (char)50:
                    button2.PerformClick();
                    break;
                case (char)51:
                    button3.PerformClick();
                    break;
                case (char)52:
                    button4.PerformClick();
                    break;
                case (char)53:
                    button5.PerformClick();
                    break;
                case (char)54:
                    button6.PerformClick();
                    break;
                case (char)55:
                    button7.PerformClick();
                    break;
                case (char)56:
                    button8.PerformClick();
                    break;
                case (char)57:
                    button9.PerformClick();
                    break;

            }

        }  
    }


}

}

Answer 1

检查窗口的PreviewKeyDown事件并做一些像这样的事情

if (e.KeyCode == Keys.NumPad0 || e.KeyCode == Keys.NumPad1)
{
   // Do what you want to do.
}

Answer 2

您可以为具有相同代码/功能的所有按钮添加相同的事件处理程序，例如：

buttonZero.Click += numberButton_Click;
buttonOne.Click += numberButton_Click;
...

buttonPlus.Click += numberButton_Click;
buttonMinus.Click += numberButton_Click;
...

private void numberButton_Click(object sender, EventArgs e)
{
   checkifequa();
   var numButton = sender as Button;
   if(numButton != null)
      textBox1.Text = textBox1.Text + numButton.Text; // supposing your num buttons have only the number as text (otherwise you could use the Tag property of buttons)
}

private void operatorButton_Click(object sender, EventArgs e)
{
   checkifequa();
   var operatorButton = sender as Button;
   if(operatorButton != null)
      textBox1.Text = textBox1.Text + operatorButton .Text; // supposing your operator buttons have only the operator as text (otherwise you could use the Tag property of button)
}
// ...

对于键盘事件，如cre-johnny07所示：你可以处理previewKeyDown事件或KeyDown事件，并执行以下操作：

private void parentControl_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.NumPad0)
        this.buttonZero.PerformClick();
    else if (e.KeyCode == Keys.NumPad1)
        this.buttonOne.PerformClick();
    // and so on... 
}

通过这种方式，在numPad ...

上键入时，您还可以获得一个很好的按键效果

Answer 3

你还可以做的是让鼠标点击事件和keydown事件指向同一件事。如果您在事件下进入控件属性，请为keydown和mouseclick选择相同的事件。只需在代码中添加“if”语句即可检查谁在调用它。

根据我的经验，程序的结构变得更加整洁。

Answer 4

我会从点击/按键处理程序中取出“业务逻辑”。另外，我会将数据存储在私有属性中，而不是TextBox的Tag中。我遗漏了你通常会拥有的验证码。

private string FirstNumber { get; set; }
private string SecondNumber { get; set; }
private bool IsSecondNumberBeingEntered { get; set; }

private Operation SelectedOperation { get; set;}
private enum Operation
{
    Add,
    Subtract,
    Multiply,
    Divide
}

private void button0_Click(object sender, EventArgs e)
{
    this.AddNumber(0);
    textBox1.Text = textBox1.Text + "0";
}

// Etc.

// In PreviewKeyDown:
if (e.KeyCode == Keys.NumPad0 || e.KeyCode == Keys.D0)
{
    this.AddNumber(0);
}

private void AddNumber(int number)
{
    if (IsSecondNumberBeingEntered)
    {
        SecondNumber += number.ToString();
    }
    else
    {
        FirstNumber += number.ToString();
    }
}

private decimal Calculate()
{
    switch (SelectedOperation)
    {
        case Operation.Add:
            return Convert.ToDecimal(FirstNumber) + Convert.ToDecimal(SecondNumber);
        case Operation.Subtract:
            return Convert.ToDecimal(FirstNumber) - Convert.ToDecimal(SecondNumber);
        // etc.
        default:
            throw new ArgumentOutOfRangeException();
    }
}

c＃如何获得keydown和按钮点击做同样的事情？

4 个答案: