从一种方法调用数组到另一种方法 [英] Call an array from one method to another method

问题描述

我有一个方法 A，我在其中创建了一个数组.现在我想在另一个方法 B 中使用该数组，并且想知道是否有可能在方法 B 中调用方法 A 并使用该数组而不是在我创建的每个方法中创建该数组.

I have a method A in which I have created an array. Now I want to use the array in another method B and was wondering if there is any possibility that I can call the method A inside method B and use the array instead of creating the array in each and every method I create.

public static void myArray() {
    String[][] resultCard =  new String[][]{ 
                { " ", "A", "B", "C"},
                { "Maths", "78", "98","55"}, 
                { "Physics", "55", "65", "88"}, 
                { "Java", "73", "66", "69"},
             };
}

public static void A() {
    //Not sure how I can include the array (myArray) here   
}

public static void B() {
    //Not sure how I can include the array (myArray) here   
}

推荐答案

这是一个文字(评论)说明说明(问题和答案):>

Here's a text (comment) illustrated explanation (both the question and the answer):

public Object[] methodA() {
    // We are method A
    // In which we create an array
    Object[] someArrayCreatedInMethodA = new Object[10];
    // And we can returned someArrayCreatedInMethodA
    return someArrayCreatedInMethodA;
}

public void methodB() {
    // Here we are inside another method B
    // And we want to use the array
    // And there is a possibility that we can call the method A inside method B
    Object[] someArrayCreatedAndReturnedByMethodA = methodA();
    // And we have the array created in method A
    // And we can use it here (in method B)
    // Without creating it in method B again
}

您编辑了您的问题并包含了您的代码.在您的代码中，数组不是在方法 A 中创建的，而是在 myArray() 中创建的，并且您没有返回它，因此它在 myArray() 方法返回(如果它被调用过).

You edited your question and included your code. In your code the array is not created in method A but in the myArray(), and you don't return it, so it is "lost" after the myArray() method returns (if it is ever called).

建议:将您的数组声明为您的类的一个属性，使其成为静态的，您可以在 a() 和 方法中将其简单地称为 resultCard代码>b():

Suggestion: declare your array as an attribute of your class, make it static, and you can simply refer to it as resultCard from both methods a() and b():

private static String[][] resultCard = new String[][] {
    { " ", "A", "B", "C"},
    { "Maths", "78", "98","55"},
    { "Physics", "55", "65", "88"},
    { "Java", "73", "66", "69"},
};

public static void A() {
    // "Not sure how I can include the array (myArray) here"
    // You can access it and work with it simply by using its name:
    System.out.println(resultCard[3][0]); // Prints "Java"
    resultCard[3][0] = "Easy";
    System.out.println(resultCard[3][0]); // Prints "Easy"
}

这篇关于从一种方法调用数组到另一种方法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！