C#桌面应用制作简易计算器，可实现数字之间的加减乘除、AC按键清屏、Del按键清除末尾数字、+/-按键取数字相反数、%按键使数字缩小100倍、=按键显示运算结果等......
页面实现效果
功能实现
布局
计算器主体使用Panel容器，然后将button控件排列放置Panel容器做为计算器按键，显示主体使用groudBox容器，然后在groudBox容器里放置一个Panel容器作为显示屏，再在Panel容器放置一个label控件用于显示输入和运算结果。
布局效果
数字按键功能
点击数字按键使其数字投射到计算器平面上，因为屏幕大小有限，所以使其数字长度大于16时，字体缩小一倍，数字长度大于30时，弹窗提示"字符长度超出范围"。
数字按键功能实现效果
数字按键功能实现代码
cs
private void button8_Click(object sender, EventArgs e)
{
string seven = "7";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;//如果前面有运算符，则先消除运算符再把数字投射到屏幕上
}
label1.Text = label1.Text + seven;//将数字投射到屏幕上
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}运算符按键功能
如果在输入运算符前未输入数字，则弹窗提示"无运算数字"；如果输入运算符前已经输入数字且symbol（运算符）为null，则清除已经输入的并且投射到屏幕上的数字并将其赋值至num1，然后将运算符赋值给symbol并投射到屏幕上；如果输入运算符前屏幕上已经显示了输入的运算符，则弹窗提示"您已输入运算符"；如果输入运算符前已经输入数字且symbol（运算符）已被赋值，则清除已经输入的并且投射到屏幕上的数字并将其赋值至num2并计算num1 运算符 num2结果并将其赋值至num1，然后将运算符赋值给symbol并投射到屏幕上。
运算符按键功能实现效果
运算符按键功能实现代码
cs
private void button4_Click(object sender, EventArgs e)
{
string divide = "÷";
if (symbol == null && label1.Text.Length<1&&num1==null)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
if(num1 == null)
{
num1 = label1.Text;
}
symbol = divide;
label1.Text = symbol;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷") {
MessageBox.Show("您已输入运算符");
}
else
{
num2 = label1.Text;
rt = double.Parse(num1) / double.Parse(num2);
num1 = rt.ToString();
symbol = divide;
label1.Text = symbol;
num2 = null;
}
}
}
}
AC按键功能
点击清除所有信息。
AC按键功能实现效果
AC按键功能实现代码
cs
private void button1_Click(object sender, EventArgs e)
{
label1.Text = null;
num1=null;
num2=null;
symbol = null;
}Del按键功能
点击清除末尾字符，如果屏幕上末尾字符显示的是输入的运算符，则点击后清除运算符并把num1的值投射到屏幕上。
Del按键功能实现效果
Del按键功能实现代码
cs
private void button2_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
label1.Text = null;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = num1;
symbol = null;
}
else
{
string del = label1.Text;
label1.Text = del.Substring(0, del.Length - 1);
if (label1.Text.Length < 30)
{
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
}
}
}+/-按键功能
点击取屏幕上数字的相反数并投射到屏幕上；但是如果点击+/-按键时屏幕上没有数字或屏幕上为运算符，则按键提示"error"（按键'.'同样效果）。
+/-按键功能实现效果
+/-按键功能实现代码
cs
private void button3_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
MessageBox.Show("error");
}
else if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
double reserve = double.Parse(label1.Text);
reserve = -reserve;
label1.Text = reserve.ToString();
}
}%按键功能
点击实现屏幕上数字缩小一百倍效果并将结果投射到屏幕上，但是如果点击%按键时屏幕上没有数字或屏幕上为运算符，则按键提示"error"。
%按键功能实现效果
%按键功能实现代码
cs
private void button20_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
MessageBox.Show("error");
}
else if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
double reserve = double.Parse(label1.Text);
reserve = reserve / 100;
label1.Text = reserve.ToString();
}
}等号按键功能
点击实现运算效果并将最终结果输出到屏幕上；如果在输入等号前输入数字但是未输入运算符，屏幕显示字符保持原来不变，不进行运算；如果在输入等号前未输入数字也未输入运算符，则弹窗提示"无运算数字"；如果只输入一个数字和一个运算符，则弹窗提示"error"。
等号按键功能实现效果
等号按键功能实现代码
cs
private void button17_Click(object sender, EventArgs e)
{
if (symbol == null && label1.Text.Length < 1)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
num1 = label1.Text;
}
else
{
if (label1.Text != null)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
num2 = label1.Text;
}
}
}
}
if (num2 != null)
{
if (symbol == "+")
{
rt = double.Parse(num1) + double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "-")
{
rt = double.Parse(num1) - double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "×")
{
rt = double.Parse(num1) * double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "÷")
{
rt = double.Parse(num1) / double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
}
}完整代码实现
cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApp计算器
{
public partial class Form1 : Form
{
string symbol, num1, num2,Num1,Num2;
double rt;
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
label1.Text = null;
num1=null;
num2=null;
symbol = null;
}
private void button2_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
label1.Text = null;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = num1;
symbol = null;
}
else
{
string del = label1.Text;
label1.Text = del.Substring(0, del.Length - 1);
if (label1.Text.Length < 30)
{
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
}
}
}
private void button3_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
MessageBox.Show("error");
}
else if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
double reserve = double.Parse(label1.Text);
reserve = -reserve;
label1.Text = reserve.ToString();
}
}
private void button4_Click(object sender, EventArgs e)
{
string divide = "÷";
if (symbol == null && label1.Text.Length<1&&num1==null)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
if(num1 == null)
{
num1 = label1.Text;
}
symbol = divide;
label1.Text = symbol;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷") {
MessageBox.Show("您已输入运算符");
}
else
{
num2 = label1.Text;
rt = double.Parse(num1) / double.Parse(num2);
num1 = rt.ToString();
symbol = divide;
label1.Text = symbol;
num2 = null;
}
}
}
}
private void button8_Click(object sender, EventArgs e)
{
string seven = "7";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;//如果前面有运算符，则先消除运算符再把数字投射到屏幕上
}
label1.Text = label1.Text + seven;//将数字投射到屏幕上
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button7_Click(object sender, EventArgs e)
{
string eight = "8";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + eight;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button6_Click(object sender, EventArgs e)
{
string nine = "9";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + nine;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button5_Click(object sender, EventArgs e)
{
string multiply = "×";
if (symbol == null && label1.Text.Length < 1 && num1 == null)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
if (num1 == null)
{
num1 = label1.Text;
}
symbol = multiply;
label1.Text = symbol;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("您已输入运算符");
}
else
{
num2 = label1.Text;
rt = double.Parse(num1) * double.Parse(num2);
num1 = rt.ToString();
symbol = multiply;
label1.Text = symbol;
num2 = null;
}
}
}
}
private void button12_Click(object sender, EventArgs e)
{
string four = "4";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + four;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button11_Click(object sender, EventArgs e)
{
string five = "5";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + five;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button10_Click(object sender, EventArgs e)
{
string six = "6";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + six;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button9_Click(object sender, EventArgs e)
{
string subtract = "-";
if (symbol == null && label1.Text.Length < 1 && num1 == null)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
if (num1 == null)
{
num1 = label1.Text;
}
symbol = subtract;
label1.Text = symbol;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("您已输入运算符");
}
else
{
num2 = label1.Text;
rt = double.Parse(num1) - double.Parse(num2);
num1 = rt.ToString();
symbol = subtract;
label1.Text = symbol;
num2 = null;
}
}
}
}
private void button16_Click(object sender, EventArgs e)
{
string one = "1";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + one;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button15_Click(object sender, EventArgs e)
{
string two = "2";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + two;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button14_Click(object sender, EventArgs e)
{
string three = "3";
if (label1.Text.Length < 30)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
label1.Text = null;
}
label1.Text = label1.Text + three;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button13_Click(object sender, EventArgs e)
{
string add = "+";
if (symbol == null && label1.Text.Length < 1 && num1 == null)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
if (num1 == null)
{
num1 = label1.Text;
}
symbol = add;
label1.Text = symbol;
}
else
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("您已输入运算符");
}
else
{
num2 = label1.Text;
rt = double.Parse(num1)+ double.Parse(num2);
num1 = rt.ToString();
symbol = add;
label1.Text = symbol;
num2 = null;
}
}
}
}
private void button20_Click(object sender, EventArgs e)
{
if (label1.Text.Length == 0)
{
MessageBox.Show("error");
}
else if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
double reserve = double.Parse(label1.Text);
reserve = reserve / 100;
label1.Text = reserve.ToString();
}
}
private void button19_Click(object sender, EventArgs e)
{
string zero = "0";
if(label1.Text.Length < 30)
{
label1.Text = label1.Text + zero;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
private void button18_Click(object sender, EventArgs e)
{
string dot = ".";
int f=label1.Text.IndexOf(".");
if(f == -1)
{
if(label1.Text.Length == 0)
{
MessageBox.Show("error");
}
else if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
if (label1.Text.Length < 30)
{
label1.Text = label1.Text + dot;
if (label1.Text.Length > 16)
{
label1.Font = new Font(label1.Font.FontFamily, 13f, label1.Font.Style);
}
else
{
label1.Font = new Font(label1.Font.FontFamily, 26f, label1.Font.Style);
}
}
else
{
MessageBox.Show("字符长度超出范围");
}
}
}
else
{
MessageBox.Show("error");
}
}
private void button17_Click(object sender, EventArgs e)
{
if (symbol == null && label1.Text.Length < 1)
{
MessageBox.Show("无运算数字");
}
else
{
if (symbol == null)
{
num1 = label1.Text;
}
else
{
if (label1.Text != null)
{
if (label1.Text == "+" || label1.Text == "-" || label1.Text == "×" || label1.Text == "÷")
{
MessageBox.Show("error");
}
else
{
num2 = label1.Text;
}
}
}
}
if (num2 != null)
{
if (symbol == "+")
{
rt = double.Parse(num1) + double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "-")
{
rt = double.Parse(num1) - double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "×")
{
rt = double.Parse(num1) * double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
else if (symbol == "÷")
{
rt = double.Parse(num1) / double.Parse(num2);
label1.Text = rt.ToString();
num1 = rt.ToString();
symbol = null;
num2 = null;
}
}
}
}
}