通过按键来移动坦克，并且解决同时按两个方向键的问题

src/com/msb/DirEnum.java

@@ -0,0 +1,11 @@
+package com.msb;
+
+/**
+ * @Author bingor
+ * @Date 2022-09-29 21:17
+ * @Description: 方向枚举
+ * @Version: 1.0
+ */
+public enum DirEnum {
+    LEFT, RIGHT, UP, DOWN
+}

src/com/msb/TankFrame.java

@@ -16,6 +16,8 @@ public class TankFrame extends Frame {
 
     private int x = 200;
     private int y = 200;
+    private DirEnum dir = DirEnum.RIGHT;
+    private static final int SPEED = 10;
 
     public TankFrame() {
 
@@ -40,7 +42,14 @@ public class TankFrame extends Frame {
     public void paint(Graphics g) {
         super.paint(g);
         g.fillRect(x, y, 50, 50);
-        x += 10;
+
+        switch (dir) {
+            case UP: y -= SPEED; break;
+            case DOWN: y += SPEED; break;
+            case LEFT: x -= SPEED; break;
+            case RIGHT: x += SPEED; break;
+            default: break;
+        }
     }
 
     //这里使用内部内的原因是，只有TankFrame用到
@@ -54,51 +63,35 @@ public class TankFrame extends Frame {
         @Override
         public void keyPressed(KeyEvent e) {
             super.keyPressed(e);
-            /*x += 10;
-            repaint();*/
             switch (e.getKeyCode()) {
-                case KeyEvent.VK_LEFT : {
-                    bL = true;
-                    break;
-                }
-                case KeyEvent.VK_RIGHT : {
-                    bR = true;
-                    break;
-                }
-                case KeyEvent.VK_UP : {
-                    bU = true;
-                    break;
-                }
-                case KeyEvent.VK_DOWN : {
-                    bD = true;
-                    break;
-                }
+                case KeyEvent.VK_LEFT : bL = true; break;
+                case KeyEvent.VK_RIGHT : bR = true; break;
+                case KeyEvent.VK_UP : bU = true; break;
+                case KeyEvent.VK_DOWN : bD = true; break;
                 default: break;
             }
+            setDir();
         }
 
         @Override
         public void keyReleased(KeyEvent e) {
             super.keyReleased(e);
             switch (e.getKeyCode()) {
-                case KeyEvent.VK_LEFT : {
-                    bL = false;
-                    break;
-                }
-                case KeyEvent.VK_RIGHT : {
-                    bR = false;
-                    break;
-                }
-                case KeyEvent.VK_UP : {
-                    bU = false;
-                    break;
-                }
-                case KeyEvent.VK_DOWN : {
-                    bD = false;
-                    break;
-                }
+                case KeyEvent.VK_LEFT : bL = false; break;
+                case KeyEvent.VK_RIGHT : bR = false; break;
+                case KeyEvent.VK_UP : bU = false; break;
+                case KeyEvent.VK_DOWN : bD = false; break;
                 default: break;
             }
+//            setDir(); //通过做了实验，现阶段就算不用这个方法，也不影响，但是按键抬起，坦克应该停止，如果还按照原来的方向移动就不对了
+        }
+
+        private void setDir() {
+            //为什么不用if-else 因为有可能是一起按两个方向键，那最后拿到哪个算哪个
+            if(bL) dir = DirEnum.LEFT;
+            if(bR) dir = DirEnum.RIGHT;
+            if(bU) dir = DirEnum.UP;
+            if(bD) dir = DirEnum.DOWN;
         }
     }