Question

我正在尝试在main中创建一个数组，使其与在main之外的方法中创建的数组相同。我想不出任何办法这样做......

这是我的代码：

public class GRID {     
    public void createGrid() {
        int N = StdIn.readInt();
        int thisarray[][] = new int[N][N];
        for (int x = 0; x < N; x++) {
            for (int y = 0; y < N; y++) {
                int n = (int) (Math.random() * 6 + 1);
                thisarray[x][y] = n;                
            }
        }

    }
    public static void main(String []args){     
        GRID g = new GRID();
        int [][] newArray = //thisarray 
    }
}

Answer 1

你在寻找这个答案吗？我已将方法的返回类型更改为int[][] 在main方法中，我们可以调用createGrid方法来获取int[][]

public class GRID {     
    public int[][] createGrid() {
        int N = StdIn.readInt();
        int thisarray[][] = new int[N][N];
        for (int x = 0; x < N; x++) {
            for (int y = 0; y < N; y++) {
                int n = (int) (Math.random() * 6 + 1);
                thisarray[x][y] = n;                
            }
        }
        return thisarray;

    }
    public static void main(String []args){     
        GRID g = new GRID();
        int [][] newArray = g.createGrid();
    }
}

如果您希望newArray基于N，请将N发送到createGrid方法。为此，您必须在createGrid方法中添加一个参数，如下所示。从StdIn.readInt()方法

中删除createGrid

public class GRID {     
    public int[][] createGrid(int N) {
        int thisarray[][] = new int[N][N];
        for (int x = 0; x < N; x++) {
            for (int y = 0; y < N; y++) {
                int n = (int) (Math.random() * 6 + 1);
                thisarray[x][y] = n;                
            }
        }
        return thisarray;

    }
    public static void main(String []args){     
        GRID g = new GRID();
        int [][] newArray = g.createGrid(StdIn.readInt());  //new array everytime on the basis of input value.
    }
}

Answer 2

将createGrid（）的返回类型从void更改为int [] []

public class GRID 
{

public int[][] createGrid() {
    int N = StdIn.readInt();
      int thisarray[][] = new int[N][N];
    for (int x = 0; x < N; x++) {
        for (int y = 0; y < N; y++) {
            int n = (int) (Math.random() * 6 + 1);
            thisarray[x][y] = n;
        }
    }
   return thisarray;
}
public static void main(String []args)
{
   GRID g = new GRID();
   int [][] newArray = g.createGrid(); 
} 
}

Answer 3

让thisarray成为该类的static实例（因为它在static main中使用）

public class GRID {

    private static int[][] thisarray;

    public void createGrid() {
        int N = StdIn.readInt();
        thisarray = new int[N][N];
        for (int x = 0; x < N; x++) {
            for (int y = 0; y < N; y++) {
                int n = (int) (Math.random() * 6 + 1);
                thisarray[x][y] = n;

            }
        }
    }

    public static void main(String []args){
        GRID g = new GRID();
        g.createGrid();
        int [][] newArray = thisarray; 
    } 
}

Answer 4

在return thisarray;方法中添加createGrid()（同时将返回类型从void更改为int[][]），在主要内容中您将拥有：

int [][] newArray = g.createGrid()

Answer 5

public class GRID {  
    //Declare your array here   
    private int thisarray[][];
    public void createGrid() {
        int N = StdIn.readInt();
        thisarray[][] = new int[N][N];
        for (int x = 0; x < N; x++) {
            for (int y = 0; y < N; y++) {
                int n = (int) (Math.random() * 6 + 1);
                thisarray[x][y] = n;                
            }
        }

    }
    public static void main(String []args){     
        GRID g = new GRID();
        //Then you can use it in the main
        int [][] newArray = thisarray; 
    }

}

main中的数组指的是main之外的数组

5 个答案: