需要在 For 循环之外将数组输出转换为字符串

Question

我正在尝试使用数组练习准备我的 Java SE 11 测试，我需要帮助让我的随机名称生成器工作。现在，我不关心名称是否“有效”（像 Xvtwg 这样真正随机的名称就可以了）。

我构建了一个循环，其中生成一个 3 到 10 之间的随机值（名称长度），然后为每个循环传递选择一个 0 到 25 之间的随机索引以获取字母表中的随机字母。所有这些都有效，我能够从循环中获取输出数组并将其转换为循环中的串联字符串。稍后当我需要调用局部变量 nameFinal 作为 set 函数的值时出现问题。

我试图在循环内部和外部声明输出字符串，但两种方式我都return“nameFinal 无法解析为变量。”我还尝试将输出数组移出循环（并重新定义其输出），但 return 相同的变量。"

我添加了一个 try/catch 块来试图更好地说明这个问题。这是我的代码：


public class Tester {
    public static void main(String[] args) {
        //Build random values
        Random rand = new Random();
        
        //Name random index 3-10 char
        int nmax = 10;
        int nmin = 3;
        int rand1 = (int)(Math.random() * (nmax - nmin + 1) + nmin);
        //Create random name from total number of letters
        //Define Array of letters
        String[] letters = {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
        //Create random index to pull a random letter over the length of the random index
        int lmax = 25;
        int lmin = 0;
        //I have also tried declaring newName and nameFinal here
        for(int i = 0; i <= rand1; i++) {
            int randl = (int)(Math.random() * (lmax - lmin + 1) + lmin);
            String[] newName;
            newName[i] = letters[i];
            String nameFinal = Arrays.toString(newName);
        }
        //Concatenate array of random letters into a "name"
        try{
            String nameFinal = Arrays.toString(newName);
            System.out.println(nameFinal);
        }catch(Exception e) {
            e.PrintStackTrace()
        }
        //Implementation omitted
    }
}

Answer 1

我稍微修改了你的代码。希望对您有所帮助！

public static void main(String[] args) {
    //Build random values
    Random rand = new Random();
    Test test = new Test();
    test.randomName();
    test.createAge();
    test.createSSN();
}

//Name random index 3-10 char
public void randomName() {
    int nmax = 10;
    int nmin = 3;
    int rand1 = (int)(Math.random() * (nmax - nmin + 1) + nmin);
    //Create random name from total number of letters
    //Define Array of letters
    String[] letters = {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};

    //Create random index to pull a random letter over the length of the random index
    int lmax = 25;
    int lmin = 0;

    ArrayList<String> name = new ArrayList<>(5);
    for(int i = 0; i <= rand1; i++) {
        int randl = (int)(Math.random() * (lmax - lmin + 1) + lmin);
        name.add(letters[rand1]);
    }
    System.out.println(name.toString());
}

//Age random number between 1 and 100
private void createAge(){
    int amax = 100;
    int amin = 1;
    int rand2 = (int)(Math.random() * (amax - amin + 1) + amin);
}

//SSN random 9 digit number
private void createSSN(){
    int smax = 999999999;
    int smin = 100000000;
    int rand3 = (int)(Math.random() * (smax - smin + 1) + smin);
}
   
}

需要在 For 循环之外将数组输出转换为字符串

Need to Convert Array Output to String Outside of a For Loop

java

arrays

for-loop

random

encapsulation