C# 中 returns 多个值的函数的方法签名

Question

我有下面的方法调用 returns 多个值，而且该函数是异步类型的。

var (averageSalary, numberOfEmployee) = await SomeCalculation(0L, 10, 0L == 10L);

现在我需要编写函数的方法签名和return类型。下面是代码：

private static void Main(string[] args)
    {
        var (averageSalary, numberOfEmployee) = await SomeCalculation(0L, 10, 0L == 10L);
    }

    public static async Task<(long averageSalary, long numberOfEmployee)> SomeCalculation(long num1, long num2, bool b)
    {
        long averageSalary = num1;
        long numberOfEmployee = num2;

        return (averageSalary, numberOfEmployee);
    }

但问题是在main方法中调用该方法时，出现以下错误。

The 'await' operator can only be used within an async method. Consider marking this method with the 'async' modifier and changing its return type to 'Task'.

谁能给我写正确方法签名的建议。

Answer 1

您的代码应如下所示：

public static async Task<(long averageSalary, long numberOfEmployee)> SomeCalculation(long num1, long num2, bool b)
{
    long averageSalary = num1;
    long numberOfEmployee = num2;

    return (averageSalary, numberOfEmployee);
}

static async Task Main(string[] args)
{
    var (averageSalary, numberOfEmployee) = await SomeCalculation(0L, 10, 0L == 10L);
}

您可能需要将 Visual Studio 中的 C# 版本重置为最新版本（7.1 或更高版本）。单击项目，单击鼠标右键，单击 "Build"，然后单击 "Advanced" 按钮。解释 here.

C# 中 returns 多个值的函数的方法签名

Method signature of the function which returns multiple value in C#

c#

return-value