### C# WinForms 小型项目示例 #### 创建一个简单的计算器应用程序 下面是一个使用C# WinForms创建的小型计算器应用程序的实现。此程序展示了如何利用WinForms提供的控件来构建用户界面，并通过事件处理逻辑完成基本算术运算。 ```csharp using System; using System.Windows.Forms; namespace SimpleCalculator { public partial class CalculatorForm : Form { private double firstNumber = 0; // 存储第一个操作数 private string operation = ""; // 存储当前选择的操作符 (+, -, *, /) public CalculatorForm() { InitializeComponent(); } private void InitializeComponent() { this.SuspendLayout(); // TextBox to display the result and input numbers textBoxResult = new TextBox { Location = new System.Drawing.Point(12, 12), Size = new System.Drawing.Size(260, 27), Font = new System.Drawing.Font("Arial", 18F, System.Drawing.FontStyle.Bold) }; Controls.Add(textBoxResult); // Buttons for digits (0-9) and operations (+,-,*,/) int buttonWidth = 65; int buttonHeight = 60; int startX = 12; int startY = 50; int rowSpacing = 10; int columnSpacing = 5; var buttonsTexts = "789/456*123+-0.".ToCharArray(); foreach (char c in buttonsTexts) { Button btn = new Button { Text = c.ToString(), Width = buttonWidth, Height = buttonHeight }; if ("+".Contains(c)) { btn.Location = new Point(startX + ((buttonWidth + columnSpacing) * 2), startY + (((buttonsTexts.Length - 1) % 4) / 4) * (buttonHeight + rowSpacing)); } else if ("-".Contains(c)) { btn.Location = new Point(startX + ((buttonWidth + columnSpacing) * 3), startY + (((buttonsTexts.Length - 1) % 4) / 4) * (buttonHeight + rowSpacing)); } else { btn.Location = new Point(startX + ((Array.IndexOf(buttonsTexts, c) % 4) * (buttonWidth + columnSpacing)), startY + (Array.IndexOf(buttonsTexts, c) / 4) * (buttonHeight + rowSpacing)); } btn.Click += OnButtonClick; Controls.Add(btn); } // Equal sign button (=) Button equalButton = new Button { Text = "=", Width = buttonWidth * 2 + columnSpacing, Height = buttonHeight }; equalButton.Location = new Point(startX + ((buttonWidth + columnSpacing) * 2), startY + (rowSpacing + buttonHeight) * 4); equalButton.Click += OnEqualClick; Controls.Add(equalButton); this.ClientSize = new System.Drawing.Size(284, 361); this.Text = "Simple Calculator"; this.ResumeLayout(false); this.PerformLayout(); } private void OnButtonClick(object sender, EventArgs e) { Button clickedButton = (Button)sender; if (!"+-*/.".Contains(clickedButton.Text)) { textBoxResult.AppendText(clickedButton.Text); } else { firstNumber = Convert.ToDouble(textBoxResult.Text); operation = clickedButton.Text; textBoxResult.Clear(); } } private void OnEqualClick(object sender, EventArgs e) { try { double secondNumber = Convert.ToDouble(textBoxResult.Text); switch(operation){ case "+": textBoxResult.Text = (firstNumber + secondNumber).ToString(); break; case "-": textBoxResult.Text = (firstNumber - secondNumber).ToString(); break; case "*": textBoxResult.Text = (firstNumber * secondNumber).ToString(); break; case "/": if(secondNumber != 0) textBoxResult.Text = (firstNumber / secondNumber).ToString(); else MessageBox.Show("Cannot divide by zero!"); break; } } catch(Exception ex) { MessageBox.Show($"Error occurred: {ex.Message}"); } } static void Main(string[] args) { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new CalculatorForm()); } private TextBox textBoxResult; } } ``` 这段代码定义了一个名为`SimpleCalculator`的应用程序，其中包含一个窗体`CalculatorForm`。该窗体包含了文本框用于显示输入数值和计算结果，以及多个按钮代表不同的数字键和运算符[^1]。当点击这些按钮时会触发相应的事件处理器方法，在这里实现了基本四则运算的功能。