java - Java多维数组/打印空值

Question

这是来自一个 10 行 4 列的数组。如何获得 if 以防止空值打印到屏幕

      for(int j = 0; j < calculation[i].length; j++)
        if (calculation[i] != null)<-------- this does nothing, however if I change it to == null nothing prints to screen
      System.out.print(calculation[i][j] + " \t");
      System.out.print("\n");

Answer 1

这将为您打印除空值之外的整个数组。

  for(int i = 0; i < calculation.length; i++)
    {
      for(int j = 0; j < calculation[i].length; j++)
      {
        if(calculation[i][j] != null)
           System.out.println(calculation[i][j] + "\t");
      }
      System.out.println("");
    }

Answer 2

calculation[i]可能不是 null 但calculation[i][j]可能是。

将您的代码更改为：

if (calculation[i][j] != null) 
      {
   //Your code.
      }