Java 字符串编辑函数循环正在跳过if语句

我正在尝试制作一个程序，让用户可以使用下面列出的3种方法来编辑字符串（替换、删除、插入），它们工作得很好。问题是，一旦我执行了第一个操作，它就会询问他们是否希望同时执行下两个操作，而不是等待下面if语句的输入

我的密码是

    StringBuilder s = new StringBuilder("");
    boolean q = true;

    System.out.print("Enter a string :");
    String c = userinput.nextLine();
    s.append(c);

    while (q = true) {

        System.out.print("would you like to replace a character? (Y/N)");
        String replace1 = userinput.nextLine();
        if (replace1.equals("Y")) {
            System.out.print("Which char would you like to replace?");
            int r = userinput.nextInt();
            System.out.print("What char would you like to replace it with?");
            String j = userinput.next();
            s.deleteCharAt(r);
            s.insert(r, j);
            System.out.println("updated string is: " + s);
        }

        System.out.println("would you like to eliminate a character? (Y/N)");
        String replace2 = userinput.nextLine();
        if (replace2.equals("Y")) {
            System.out.print("Which char would you like to eliminate?");
            int r = userinput.nextInt();
            s.deleteCharAt(r);
            System.out.println("updated string is: " + s);
        }
        System.out.println("would you like to insert a character? (Y/N)");
        String replace3 = userinput.nextLine();
        if (replace3.equals("Y")) {
            System.out.print("Which char would you like to insert?");
            String i = userinput.next();
            System.out.print("Where would you like to insert it?");
            int r = userinput.nextInt();
            s.insert(r, i);
            System.out.println("updated string is: " + s);
        }
        System.out.println("would you like to edit more? (Y/N)");
        String quit = userinput.nextLine();
        if (quit.equals("N")) {
            System.out.println("you have exited the string editor");
            System.exit(0);
        }

    }

}
}

• 输入字符串：sam是否要替换字符？（是/否）是
• 您要替换哪个字符？0
• 你想喝点什么 将其替换为？B
• 更新的字符串是：Bam您想消除吗 一个角色？（是/否）
• 是否要插入一个字符？（是/否）

---

它不允许我选择删除任何字符，因为当循环条件错误时，它跳过到最后一个操作用于分配值，'='用于比较。我尝试将userinput.nextLine（）更改为userinput.next（），一切正常

也可以尝试使用equalsIgnoreCase而不是equals方法

    Scanner userinput = new Scanner(System.in);
    StringBuilder s = new StringBuilder("");
    boolean q = true;

    System.out.print("Enter a string :");
    String c = userinput.next();
    s.append(c);

    while (q == true) {

        System.out.print("would you like to replace a character? (Y/N)");
        String replace1 = userinput.next();
        if (replace1.equals("Y")) {
            System.out.print("Which char would you like to replace?");
            int r = userinput.nextInt();
            System.out.print("What char would you like to replace it with?");
            String j = userinput.next();
            s.deleteCharAt(r);
            s.insert(r, j);
            System.out.println("updated string is: " + s);
        }

        System.out.println("would you like to eliminate a character? (Y/N)");
        String replace2 = userinput.next();
        if (replace2.equals("Y")) {
            System.out.print("Which char would you like to eliminate?");
            int r = userinput.nextInt();
            s.deleteCharAt(r);
            System.out.println("updated string is: " + s);
        }
        System.out.println("would you like to insert a character? (Y/N)");
        String replace3 = userinput.next();
        if (replace3.equals("Y")) {
            System.out.print("Which char would you like to insert?");
            String i = userinput.next();
            System.out.print("Where would you like to insert it?");
            int r = userinput.nextInt();
            s.insert(r, i);
            System.out.println("updated string is: " + s);
        }
        System.out.println("would you like to edit more? (Y/N)");
        String quit = userinput.next();
        if (quit.equals("N")) {
            System.out.println("you have exited the string editor");
            System.exit(0);
        }

    }

---

while（q=true）

对您来说是个错误吗代码您如何知道它跳过了if语句？你调试过了吗？

扫描仪

和

nextLine

next

和

nextInt

通常非常容易出错，因为控制台是基于行的。幸运的是，您可以测试代码片段。