Java - While循环不起作用后的IF语句 [英] Java - IF statement after While loop not working

问题描述

谢谢大家，并且出现了新的问题。

Thanks guys, and, new problem arises.

即使列表和用户输入正确，它仍会打印出来你的找不到电影或/和剧院。

Even if the list and user input is correct, it will still print out "Your movie or/and theatre cannot be found."

我发现了有关问题的事情。当列表中的任何一个（电影0-1项目和剧院0-1项目）中有1个项目时，它将无法打印出来无法找到您的电影或/和影院。

Things that I have found out about the problem. When there is 1 item in either one of the list (movie 0-1 item & theatre 0-1 item), it will not print out "Your movie or/and theatre cannot be found."

但是当其中任何一个中有超过1个项目时（电影1项目和剧院2或电影2&剧院1） ，它将打印出 if（found == false）语句。

But when there is more than 1 item in either 1 of them (movie 1 item & theatre 2 or movie 2 & theatre 1), it will print out the if(found == false) statement.

public void addScreening(){
    System.out.println("-ADD NEW SCREENING-");
    String mTitle = Helper.readString("Enter movie title > ");
    String tName = Helper.readString("Enter theatre name > ");

    boolean found = true;

    while(found == true){
    for (int i = 0; i < movies.size(); i++) {
        for (int j = 0; j < theatres.size(); j++) {
            if ((movies.get(i).getTitle().contains(mTitle) || mTitle.contains(movies.get(i).getTitle())) && 
                    (theatres.get(j).getName().contains(tName) || tName.contains(theatres.get(j).getName()))) {

                int year = Helper.readInt("Enter year > ");
                int month = Helper.readInt("Enter month > ");
                int day = Helper.readInt("Enter day > ");
                int hour = Helper.readInt("Enter hour > ");
                int min = Helper.readInt("Enter min > ");

                screenings.add(new MovieScreening(Helper.thisDate(year,
                        month, day, hour, min), movies.get(i),theatres.get(j), 0));
                System.out.println("Added successfully");

        }else if((!movies.get(i).getTitle().contains(mTitle) || !mTitle.contains(movies.get(i).getTitle())) 
                || (!theatres.get(j).getName().contains(tName) || !tName.contains(theatres.get(j).getName()))){

        found = false;

    }
        }

    }break;
    }if (found == false){
    System.out.println("Your movie or/and theatre cannot be found.");
    found = true;
    }
}

输出

-ADD NEW SCREENING-
Enter movie title > 3
Enter theatre name > 3
Enter year > 3
Enter month > 3
Enter day > 3
Enter hour > 3
Enter min > 3
Added successfully
Your movie or/and theatre cannot be found.

推荐答案

只需更改

if (found = false)

to

if (found == false)

//OR

if (!found)

您使用的是赋值运算符（ = ）而不是比较（ == ）。这是一个常见的拼写错误，在很多情况下最容易使用这些格式。

You were using assignment operator (=) instead of comparison (==). This is a common typo and in many cases it is easiest to use these formats.

if (found) {}  // if (found == true)
if (!found) {} // if (found == false)

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