当我在C#窗体应用程序上按Return时，Windows Ding
本文关键字：Return Ding Windows 程序上 应用程序 窗体 应用 | 更新日期: 2023-09-27 18:28:01
我必须为我的C#类制作这个基于方法的计算器。我使用的是VisualStudio2010，任务的一部分是在用户按下回车键时让"Calculate"按钮方法运行。
我以前在VS中也这样做过，但由于某种原因，这次当我尝试输入键时，它一直在响。
这是我的密码。我不认为这与代码有任何关系，但我不知道问题是什么，所以我提出它只是以防万一。
非常感谢您的帮助。非常感谢。
{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 Week4Calculator
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnCalculate_Click(object sender, EventArgs e)
{
double operand1 = Convert.ToDouble(txOperand1.Text);
double operand2 = Convert.ToDouble(txtOperand2.Text);
string operation = txtOperator.Text;
double result = 0;
// Verify user input is a valid operator. If valid, run getCalculation method and
// output result to result text box. If invalid, display error message.
if (operation == "/" || operation == "*" || operation == "+" || operation == "-")
{
result = getCalculation (operand1, operand2, operation);
txtResult.Text = result.ToString();
}
else{
txtResult.Text = "ERROR";
lblError.Text = "Please enter a valid operator:'nUse: + - / *";
}
}
//Calulate 2 Operands based on input from user.
public double getCalculation(double num1, double num2, string sign)
{
double answer = 0;
switch (sign)
{
case "/":
answer = num1 / num2;
break;
case "*":
answer = num1 * num2;
break;
case "+":
answer = num1 + num2;
break;
case "-":
answer = num1 - num2;
break;
}
return answer;
}
// Clears Result text box if any new input is typed into the other 3 fields.
private void txOperand1_TextChanged(object sender, EventArgs e)
{
txtResult.Text = "";
}
private void txtOperator_TextChanged(object sender, EventArgs e)
{
txtResult.Text = "";
}
private void txtOperand2_TextChanged(object sender, EventArgs e)
{
txtResult.Text = "";
}
private void btnExit_Click(object sender, EventArgs e)
{
this.Close();
}
}
当您的一个文本框具有焦点时，就会发生这种情况。它提醒你，它不知道如何使用回车键。只有当框的MultiLine属性设置为true时，它才有意义。当然，它还没有设定。
Enter键是特殊的，与Escape键一起用于操作窗口的默认按钮。你有一个，你喜欢你的计算按钮作为你的默认按钮。因此，在设计器中选择表单并更改AcceptButton属性，从组合框中选择"计算"按钮。
不要忘记添加代码，以检查文本框中是否有可以转换为数字的有效字符串，例如double。TryPasse（）。
private void btn_equal_Click(object sender, EventArgs e)
{
//this is counter is for the for the count how many time equal button is press
intCountEqual++;
if (strOperators == "")
{
if(txt_screen.Text.Contains("0.00000000")||txt_screen.Text.Contains("0.0"))
{
txt_screen.Text = "0";
lbl_history.Text = "0" + "=";
}
else
{
decValue1 = Convert.ToDecimal(txt_screen.Text);
txt_screen.Text = Convert.ToString(decValue1);
lbl_history.Text = txt_screen.Text + "=";
}
}
//If the error is display then nothing will change
else if (intCountError > 0)
{
btn_clear.PerformClick();
}
else
{
try
{
//this switch case is check the what operation is perform
switch (strOperators)
{
case "+":
//if the intCountEqual greaterthan 1 then perform if part other wise perform else part
if (intCountEqual > 1)
{
//if the result is display then press equel so this operation is perfrom
//value2 + result = new result like 10+20 = 30 (Press equal so result is 30+20=50)
lbl_history.Text = Convert.ToString(decResult) + "+" + Convert.ToString(decValue2) + "=";
decResult = decValue2 + decResult;
txt_screen.Text = Convert.ToString(decResult);
}
else
{
//if the result is not display that mean first you press equal button then perfrom this block
//value1 + value2 = result that mean 10+20 = 30
decValue2 = Convert.ToDecimal(txt_screen.Text);
lbl_history.Text += Convert.ToString(decValue2) + "=";
decResult = decValue1 + decValue2;
}
break;
case "-":
if (intCountEqual > 1)
{
lbl_history.Text = Convert.ToString(decResult) + "-" + Convert.ToString(decValue2) + "=";
decResult = decResult - decValue2;
txt_screen.Text = Convert.ToString(decResult);
}
else
{
decValue2 = Convert.ToDecimal(txt_screen.Text);
lbl_history.Text += Convert.ToString(decValue2) + "=";
decResult = decValue1 - decValue2;
}
break;
case "*":
if (intCountEqual > 1)
{
lbl_history.Text = Convert.ToString(decResult) + "*" + Convert.ToString(decValue2) + "=";
decResult = decResult * decValue2;
txt_screen.Text = Convert.ToString(decResult);
}
else
{
decValue2 = Convert.ToDecimal(txt_screen.Text);
lbl_history.Text += Convert.ToString(decValue2) + "=";
decResult = decValue1 * decValue2;
}
break;
case "/":
if (intCountEqual > 1)
{
lbl_history.Text = Convert.ToString(decResult) + "/" + Convert.ToString(decValue2) + "=";
decResult = decResult / decValue2;
txt_screen.Text = Convert.ToString(decResult);
}
else
{
decValue2 = Convert.ToDecimal(txt_screen.Text);
lbl_history.Text += Convert.ToString(decValue2) + "=";
if (decValue2 == 0)
{
intCountError++;
lbl_history.Text = decValue1 + strOperators + decValue2 + "=";
txt_screen.Font = new Font(txt_screen.Text, 14, FontStyle.Bold);
txt_screen.Text = "Divide by zero is not possible";
}
else
{
decResult = decValue1 / decValue2;
}
}
break;
}
//First result is generat then change in round
decResult = Math.Round(decResult, 4);
//check the length of our result and store in the result variable
int result = length_funtion(Convert.ToString(decResult));
//If first check the operand_2 and operator is / then generate error
if (decValue2 == 0 && strOperators == "/")
{
intCountError++;
lbl_history.Text = decValue1 + strOperators + decValue2 + "=";
txt_screen.Font = new Font(txt_screen.Text, 14, FontStyle.Bold);
txt_screen.Text = "Divide by zero is not possible";
}
else
{
//if result length is 9 then display other wise generate error
if (result <= 9)
{
txt_screen.Text = Convert.ToString(decResult);
}
else
{
intCountError++;
txt_screen.Text = "Result is out of the range";
txt_screen.Font = new Font(txt_screen.Text, 18, FontStyle.Bold);
lbl_history.Text = "";
}
}
}
catch
{
txt_screen.Text = "Invalid Input";
}
}
}