如何在C#方法中打印多个值？

我想通过PrintStudentDetails（string first、string last、string birthday）方法打印GetStudentInformation（）方法中的值。请查看以下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Module3_HomeWork
{
    class Program
    {
        static void GetStudentInformation()
        {
            Console.WriteLine("Enter the student's first name: ");
            string firstName = Console.ReadLine();
            Console.WriteLine("Enter the student's last name: ");
            string lastName = Console.ReadLine();
            Console.WriteLine("Enter the student's birthdate: ");
            DateTime birthdate = Convert.ToDateTime(Console.ReadLine());
            Console.WriteLine("Enter the student's address line 1: ");
            string add1 = Console.ReadLine();
            Console.WriteLine("Enter the student's address line 2: ");
            string add2 = Console.ReadLine();
            Console.WriteLine("Enter the student's city: ");
            string city = Console.ReadLine();
            Console.WriteLine("Enter the student's state: ");
            string state = Console.ReadLine();
            Console.WriteLine("Enter the student's zip code: ");
            int zip = Convert.ToInt32(Console.ReadLine());
            Console.WriteLine("Enter the student's country: ");
            string country = Console.ReadLine();
        }
        static void PrintStudentDetails(string first, string last, string birthday)
        {
            Console.WriteLine("{0} {1} was born on: {2}", first, last, birthday);
        }
        static void Main(string[] args)
        {
            GetStudentInformation();
            PrintStudentDetails(first, last, birthday);
        }

        public static string first { get; set; }

        public static string last { get; set; }

        public static string birthday { get; set; }
    }
}

如何仅使用方法而不使用类打印值？我对它进行了研究，发现了关于

out

和

ref

，任何帮助或指导都将不胜感激

---

关于

我不太清楚您所说的仅按方法而非类打印值是什么意思。但我想下面的例子可以帮到你

void PrintDetails(ref string s1, ref string s2, ref string s3)
{ 
  s1 = "Some text goes here";
  s2 = myNumber.ToString();
  s3 = "some more text";
}

现在调用此函数时，只需使用以下语法：

public void SomeOtherFunction()
{
  string sMyValue1 = null;
  string sMyValue2 = null;
  string sMyValue3 = null;

  PrintDetails(sMyValue1, sMyValue2, sMyValue3);
  //Now you have all the values inside your local variable. 
}

---

如果您只想输入名字、姓氏和出生日期，然后输出它们，您可以更改以下三行：

string firstName = Console.ReadLine();
string lastName = Console.ReadLine();
DateTime birthdate = Convert.ToDateTime(Console.ReadLine());

对下列事项：

first = Console.ReadLine();
last = Console.ReadLine();
birthday = Convert.ToDateTime(Console.ReadLine());

class Program
{
    static void GetStudentInformation(out string first, out string last, out string birthday)
    {
        Console.WriteLine("Enter the student's first name: ");
        first = Console.ReadLine();
        Console.WriteLine("Enter the student's last name: ");
        last = Console.ReadLine();
        Console.WriteLine("Enter the student's birthdate: ");
        birthday = Convert.ToDateTime(Console.ReadLine());
    }
    static void PrintStudentDetails(string first, string last, string birthday)
    {
        Console.WriteLine("{0} {1} was born on: {2}", first, last, birthday);
    }
    static void Main(string[] args)
    {
        string first, last, birthday;
        GetStudentInformation(out first, out last, out birthday);
        PrintStudentDetails(first, last, birthday);
    }
}

然后，您的程序应该按预期运行

但既然您提到了

out

和

ref

，那么您真正想要的可能是：

first = Console.ReadLine();
last = Console.ReadLine();
birthday = Convert.ToDateTime(Console.ReadLine());

class Program
{
    static void GetStudentInformation(out string first, out string last, out string birthday)
    {
        Console.WriteLine("Enter the student's first name: ");
        first = Console.ReadLine();
        Console.WriteLine("Enter the student's last name: ");
        last = Console.ReadLine();
        Console.WriteLine("Enter the student's birthdate: ");
        birthday = Convert.ToDateTime(Console.ReadLine());
    }
    static void PrintStudentDetails(string first, string last, string birthday)
    {
        Console.WriteLine("{0} {1} was born on: {2}", first, last, birthday);
    }
    static void Main(string[] args)
    {
        string first, last, birthday;
        GetStudentInformation(out first, out last, out birthday);
        PrintStudentDetails(first, last, birthday);
    }
}

---

如果您确实希望方法以这种方式返回多个值，那么使用

out

或

ref

关键字将帮助您从方法返回多个值，但使用属性可能是更好的解决方案。无论如何，这就是使用

out

关键字的效果：

static void GetStudentInformation(out string firstName, out string lastName, out DateTime birthDate,
    out string add1, out string add2, out string city, out string state, out int zip, out string country)
{
    Console.WriteLine("Enter the student's first name: ");
    firstName = Console.ReadLine();
    Console.WriteLine("Enter the student's last name: ");
    lastName = Console.ReadLine();
    Console.WriteLine("Enter the student's birthdate: ");
    birthDate = Convert.ToDateTime(Console.ReadLine());
    Console.WriteLine("Enter the student's address line 1: ");
    add1 = Console.ReadLine();
    Console.WriteLine("Enter the student's address line 2: ");
    add2 = Console.ReadLine();
    Console.WriteLine("Enter the student's city: ");
    city = Console.ReadLine();
    Console.WriteLine("Enter the student's state: ");
    state = Console.ReadLine();
    Console.WriteLine("Enter the student's zip code: ");
    zip = Convert.ToInt32(Console.ReadLine());
    Console.WriteLine("Enter the student's country: ");
    country = Console.ReadLine();
}
static void PrintStudentDetails(string first, string last, string birthday)
{
    Console.WriteLine("{0} {1} was born on: {2}", first, last, birthday);
}

static void Main(string[] args)
{
    string firstName, lastName, add1, add2, city, state, country;
    DateTime birthDate;
    int zip;

    GetStudentInformation(out firstName, out lastName, out birthDate, out add1, out add2, out city, out state, out zip, out country);
    PrintStudentDetails(firstName, lastName, birthDate.ToShortDateString());
}

---

你也可以用

ref

关键字替换所有的关键字，你会得到同样的效果。在通过引用将变量传递给GetStudentInformation方法之前，只需将变量初始化为某个值。

使用属性而不是局部变量