动态创建X个类对象

本文关键字:对象 创建 动态 | 更新日期: 2023-09-27 18:22:51

背景。。。

比方说我有一门课叫汽车。我们只需要存储汽车名称和ID。还可以说,我有一个基于管理类的管理页面,我在一个名为totalCars 的int中设置了要创建的汽车总数

问题是:如何动态地将汽车创建为可以从代码中任何地方访问的字段,同时根据totalCars中的数字创建汽车总数?

示例代码:

      Cars car1 = new Cars();
      int totalCars;
      //Somehow I want to create cars objects/fields based on the 
      //number in the totalCars int
      protected void Page_Load(object sender, EventArgs e)
      {
          car1.Name = "Chevy";
          car1.ID = 1;
      }
      protected void Button1_Click(object sender, EventArgs e)
      {
         TextBox1.Text = car1.Name.ToString();
         //this is just a sample action.
      }

动态创建X个类对象

这应该是一个技巧:

int CarCount = 100;
Car[] Cars = Enumerable
            .Range(0, CarCount)
            .Select(i => new Car { Id = i, Name = "Chevy " + i })
            .ToArray();

问候GJ

编辑

如果你只是想知道你会如何做这样的事情(你不应该做),试试这个:

using System.IO;
namespace ConsoleApplication3 {
    partial class Program {
        static void Main(string[] args) {
            Generate();
        }
        static void Generate() {
            StreamWriter sw = new StreamWriter(@"Program_Generated.cs");
            sw.WriteLine("using ConsoleApplication3;");
            sw.WriteLine("partial class Program {");
            string template = "'tCar car# = new Car() { Id = #, Name = '"Car #'" };";
            for (int i = 1; i <= 100; i++) {
                sw.WriteLine(template.Replace("#", i.ToString()));
            }
            sw.WriteLine("}");
            sw.Flush();
            sw.Close();
        }
    }    
    class Car {
        public int Id { get; set; }
        public string Name { get; set; }
    }
}

注意关键字partial class,这意味着您可以拥有一个跨越多个源文件的类。现在,您可以手动编写一个代码,然后生成另一个。

如果您运行此代码,它将生成以下代码:

using ConsoleApplication3;
partial class Program {
    Car car1 = new Car() { Id = 1, Name = "Car 1" };
    Car car2 = new Car() { Id = 2, Name = "Car 2" };
    ...
    Car car99 = new Car() { Id = 99, Name = "Car 99" };
    Car car100 = new Car() { Id = 100, Name = "Car 100" };
}

您可以将此代码文件添加到您的解决方案中(右键单击project..添加现有..)并对其进行编译。现在您可以使用这些变量car1。。car100.

使用List<Cars>:

  List<Cars> cars = new List<Cars>();
  int totalCars;
  protected void Page_Load(object sender, EventArgs e)
  {
      cars = new List<Cars>();
      for(int i=0; i<totalCars; i++)
      {  
           cars.Add(
              new Cars()
                {
                  Name = "Car #" + i;
                  ID = i;
                }
              );
      }          
  }