c# - 如何在Task中传递多个参数

Question

我有一个函数 GetPivotedDataTable(data, "date", "id", "flag") 以 Pivoted 格式返回数据。我想使用Task调用这个方法，但是如何在Task中传递多个参数。

Answer 1

您可以使用 lambda 表达式或 Func 来传递参数:)

public Form1()
{
    InitializeComponent();

    Task task = new Task(() => this.GetPivotedDataTable("x",DateTime.UtcNow,1,"test"));
    task.Start();
}

public void GetPivotedDataTable(string data, DateTime date, int id, string flag)
{
    // Do stuff
}

Answer 2

如果您的参数是不同类型的，您可以使用对象数组，然后类型转换回原始类型。

查看此控制台应用程序示例：

    static void Main(string[] args)
    {
        var param1String = "Life universe and everything";
        var param2Int = 42;

        var task = new Task((stateObj) =>
            {
                var paramsArr = (object[])stateObj; // typecast back to array of object

                var myParam1String = (string)paramsArr[0]; // typecast back to string 
                var myParam2Int = (int)paramsArr[1]; // typecast back to int 

                Console.WriteLine("");
                Console.WriteLine(string.Format("{0}={1}", myParam1String, myParam2Int));
            },
            new object[] { param1String, param2Int } // package all params in an array of object
        );

        Console.WriteLine("Before Starting Task");
        task.Start();
        Console.WriteLine("After Starting Task");

        Console.ReadKey(); 
    }

Answer 3

您可以创建一个辅助类来保存您在任务中需要的所有参数。

Answer 4

您也可以使用“参数”。检查 c# 参数信息

public class MyClass
{
    public static void UseParams(params int[] list)
    {
        for (int i = 0; i < list.Length; i++)
        {
            Console.Write(list[i] + " ");
        }
        Console.WriteLine();
    }

    public static void UseParams2(params object[] list)
    {
        for (int i = 0; i < list.Length; i++)
        {
            Console.Write(list[i] + " ");
        }
        Console.WriteLine();
    }

    static void Main()
    {
        // You can send a comma-separated list of arguments of the 
        // specified type.
        UseParams(1, 2, 3, 4);
        UseParams2(1, 'a', "test");

        // A params parameter accepts zero or more arguments.
        // The following calling statement displays only a blank line.
        UseParams2();

        // An array argument can be passed, as long as the array
        // type matches the parameter type of the method being called.
        int[] myIntArray = { 5, 6, 7, 8, 9 };
        UseParams(myIntArray);

        object[] myObjArray = { 2, 'b', "test", "again" };
        UseParams2(myObjArray);

        // The following call causes a compiler error because the object
        // array cannot be converted into an integer array.
        //UseParams(myObjArray);

        // The following call does not cause an error, but the entire 
        // integer array becomes the first element of the params array.
        UseParams2(myIntArray);
    }
}


/*
Output:
    1 2 3 4
    1 a test

    5 6 7 8 9
    2 b test again
    System.Int32[]
*/

Answer 5

您可以使用元组

Task<Tuple<Tuple<Parame1,Parame2,Parame....>> Func()
{

}


var r = await Func();
r.Item1;
r.Item2;
r.Item.....