Question

我希望这段代码在每个循环中增加值assignId和assignSales 1和5000，但是从111和25000开始。我不能只改变值吗？这是代码：

package Salesperson;

public class DemoSalesperson2 
{

    public static void main(String[] args) 
    {
        int assignId = 111;
        double assignSales = 25000;
        Salesperson salesperson1 = new Salesperson(assignId, assignSales);
        Salesperson[] salesperson = new Salesperson[10];

        for(int i = 0; i < salesperson.length; i++)

            System.out.println("Salesperson " + i + " has ID #" + salesperson1.getId() + " and annual sales of $" + salesperson1.getSales());
            Salesperson salesperson2 = new Salesperson(assignId + 1, assignSales + 5000);
    }
}

Answer 1

如果我理解你要做什么，那么你打算填充salesperson（数组）：

我会将其重命名为salespeople。
我会计算id（id = assignId + i）和sales（sales = assignSales + 5000i）。
我更喜欢格式化的IO。

像

int assignId = 111;
double assignSales = 25000;
Salesperson[] salespeople = new Salesperson[10];
for (int i = 0; i < salespeople.length; i++) {
    salespeople[i] = new Salesperson(assignId + i, assignSales + (5000 * i));
    System.out.printf("Salesperson %d has ID #%d and annual sales of $%.02f%n",
            i, salespeople[i].getId(), salespeople[i].getSales());
}

哪个输出：

Salesperson 0 has ID #111 and annual sales of $25000.00
Salesperson 1 has ID #112 and annual sales of $30000.00
...
Salesperson 9 has ID #120 and annual sales of $70000.00

Answer 2

你的代码现在可能无法正常工作，因为for循环的主体周围没有大括号，正如@ElliottFrisch在上面的评论中指出的那样。

更改

for(int i = 0; i < salesperson.length; i++)
    System.out.println("Salesperson " + i + " has ID #" + salesperson1.getId() + " and annual sales of $" + salesperson1.getSales());
    Salesperson salesperson2 = new Salesperson(assignId + 1, assignSales + 5000);

到

 for(int i = 0; i < salesperson.length; i++) {
        System.out.println("Salesperson " + i + " has ID #" + salesperson1.getId() + " and annual sales of $" + salesperson1.getSales());
        Salesperson salesperson2 = new Salesperson(assignId + 1, assignSales + 5000);
 }

除非您包含大括号，否则编译器将假定只有下一个语句（直到下一个;）是循环体，并且之后的所有其他语句都是而不是部分循环。

因此，在您提供的示例中，代码会在每次迭代时打印一些内容，但在退出循环之前不会递增值。

Answer 3

在for循环，if语句等中包含多行时，需要使用括号。此外，您需要增加值本身，而不是简单地添加到您拥有它们的基值。 assignId + = 1与执行assignId = assignId + 1相同。如果在您的情况下不执行+ =，它将始终为Salesperson对象提供相同的编号，对于assignId为112，对于assignSales为3000。您也总是打印出相同的值，因为您使用相同的Salesperson对象，您应该使用salesperson2对象并在创建后打印出内容。

//for each iteration we need to increment assignId and assignSales
for(int i = 0; i < salesperson.length; i++)
{
    //increment the variables themselves before passing to the objects
    assignId += 1;
    assignSales += 5000;
    Salesperson salesperson2 = new Salesperson(assignId, assignSales);
    System.out.println("Salesperson " + i + " has ID #" + salesperson2.getId() + " and annual sales of $" + salesperson2.getSales());

}//need second bracket to include more than one line in for loop

Answer 4

我明白了。我需要在for循环中启动salesperson1并将值设置为i，然后它将在循环中添加值。

public static void main(String[] args) 
{
    final int SALES_INCREASE = 5000;
    int assignId = 111;
    double assignSales = 25000;
    Salesperson[] salespeople = new Salesperson[10];

    for(int i = 0; i < salespeople.length; i++)
    {
        salespeople[i] = new Salesperson(assignId, assignSales);
        assignId += 1;
        assignSales += SALES_INCREASE;
        System.out.println("Salesperson " + i + " has ID #" + salespeople[i].getId() + 
                " and annual sales of $" + salespeople[i].getSales());
    }
}

Answer 5

只需将其更改为assignSales + = 5000和assignId + = 1。

在For循环中递增数组值

5 个答案: