21xrx.com
2024-12-23 01:46:41 Monday
登录
文章检索 我的文章 写文章
「教程」利用Java编写简易计算器代码 让计算更方便！
2023-06-19 16:24:12 深夜i     --     --

今天我来教大家如何用Java编写一个简易计算器代码，让计算变得更加方便快捷。

首先，我们需要先了解计算器的基本功能，即加、减、乘、除四个基本运算。在Java中，可以用四个操作符表示这四个运算，加法为“+”，减法为“-”，乘法为“*”，除法为“/”。

接下来，我们需要为计算器创建一个界面。可以使用JavaFX或Swing等工具创建，这里以JavaFX为例：



import javafx.application.Application;


import javafx.geometry.Insets;


import javafx.scene.Scene;


import javafx.scene.control.Button;


import javafx.scene.control.Label;


import javafx.scene.control.TextField;


import javafx.scene.layout.GridPane;


import javafx.stage.Stage;


public class Calculator extends Application {


  private TextField tfNum1 = new TextField();


  private TextField tfNum2 = new TextField();


  private TextField tfResult = new TextField();


  private Button btAdd = new Button("+");


  private Button btSubtract = new Button("-");


  private Button btMultiply = new Button("*");


  private Button btDivide = new Button("/");


  private Button btClear = new Button("清空");


  @Override


  public void start(Stage primaryStage) {


    GridPane gridPane = new GridPane();


    gridPane.setHgap(5);


    gridPane.setVgap(5);


    gridPane.setPadding(new Insets(5, 5, 5, 5));


    gridPane.add(new Label("数字1："), 0, 0);


    gridPane.add(tfNum1, 1, 0);


    gridPane.add(new Label("数字2："), 0, 1);


    gridPane.add(tfNum2, 1, 1);


    gridPane.add(new Label("结果："), 0, 2);


    gridPane.add(tfResult, 1, 2);


    gridPane.add(btAdd, 0, 3);


    gridPane.add(btSubtract, 1, 3);


    gridPane.add(btMultiply, 0, 4);


    gridPane.add(btDivide, 1, 4);


    gridPane.add(btClear, 1, 5);


    btAdd.setOnAction(e -> add());


    btSubtract.setOnAction(e -> subtract());


    btMultiply.setOnAction(e -> multiply());


    btDivide.setOnAction(e -> divide());


    btClear.setOnAction(e -> clear());


    Scene scene = new Scene(gridPane);


    primaryStage.setScene(scene);


    primaryStage.setTitle("简易计算器");


    primaryStage.show();


  }


  private void add() {


    double num1 = Double.parseDouble(tfNum1.getText());


    double num2 = Double.parseDouble(tfNum2.getText());


    double result = num1 + num2;


    tfResult.setText(String.valueOf(result));


  }


  private void subtract() {


    double num1 = Double.parseDouble(tfNum1.getText());


    double num2 = Double.parseDouble(tfNum2.getText());


    double result = num1 - num2;


    tfResult.setText(String.valueOf(result));


  }


  private void multiply() {


    double num1 = Double.parseDouble(tfNum1.getText());


    double num2 = Double.parseDouble(tfNum2.getText());


    double result = num1 * num2;


    tfResult.setText(String.valueOf(result));


  }


  private void divide() {


    double num1 = Double.parseDouble(tfNum1.getText());


    double num2 = Double.parseDouble(tfNum2.getText());


    double result = num1 / num2;


    tfResult.setText(String.valueOf(result));


  }


  private void clear() {


    tfNum1.setText("");


    tfNum2.setText("");


    tfResult.setText("");


  }


  public static void main(String[] args) {


    launch(args);


  }


}

该代码创建了一个包含两个输入框、一个输出框和五个按钮的界面，分别表示两个数字、结果和四个基本运算，还包括一个清空按钮。

接下来我们需要为五个按钮分别添加事件，实现对结果的计算和清空操作。



btAdd.setOnAction(e -> add());


btSubtract.setOnAction(e -> subtract());


btMultiply.setOnAction(e -> multiply());


btDivide.setOnAction(e -> divide());


btClear.setOnAction(e -> clear());


...


private void add() {


  double num1 = Double.parseDouble(tfNum1.getText());


  double num2 = Double.parseDouble(tfNum2.getText());


  double result = num1 + num2;


  tfResult.setText(String.valueOf(result));


}


private void subtract() {


  double num1 = Double.parseDouble(tfNum1.getText());


  double num2 = Double.parseDouble(tfNum2.getText());


  double result = num1 - num2;


  tfResult.setText(String.valueOf(result));


}


private void multiply() {


  double num1 = Double.parseDouble(tfNum1.getText());


  double num2 = Double.parseDouble(tfNum2.getText());


  double result = num1 * num2;


  tfResult.setText(String.valueOf(result));


}


private void divide() {


  double num1 = Double.parseDouble(tfNum1.getText());


  double num2 = Double.parseDouble(tfNum2.getText());


  double result = num1 / num2;


  tfResult.setText(String.valueOf(result));


}


private void clear() {


  tfNum1.setText("");


  tfNum2.setText("");


  tfResult.setText("");


}

现在，我们用这个简易计算器代码进行计算时可以输入数字，然后点击 +、-、*、/符号进行对应运算，清空按钮可清空所有数字和结果。

最后，我们来总结一下本文讲解的关键词：

1. Java编程

2. 简易计算器

3. 计算基本运算

  
  

评论区

{{item['qq_nickname']}}
()
回复
回复