如何在下面的代码片段中调用静态异步函数答案

【问题标题】：How to call static async function in the below code snippet如何在下面的代码片段中调用静态异步函数
【发布时间】：2017-07-22 10:37:08
【问题描述】：

public static async Task InvokeRequestResponseService( string pstrRequest)
        {
            ServiceConnect objServiceConnect = new ServiceConnect();
            using (var client = new HttpClient())
            {
                var scoreRequest = new
                {
                    Inputs = new Dictionary<string, InputOutputTable>() {
                        {
                            "input1",
                            new InputOutputTable()
                            {
                                ColumnNames = new string[] {"Assignment group", "Short description"},
                                Values = new string[,] {  { "", pstrRequest },  { "", "" },  }
                            }
                        },
                    },
                    GlobalParameters = new Dictionary<string, string>()
                    {
                    }
                };
                const string apiKey = "Some API Key"; // Replace this with the API key for the web service
                client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);

                client.BaseAddress = new Uri("Some Uri");

                // WARNING: The 'await' statement below can result in a deadlock if you are calling this code from the UI thread of an ASP.Net application.
                // One way to address this would be to call ConfigureAwait(false) so that the execution does not attempt to resume on the original context.
                // For instance, replace code such as:
                //      result = await DoSomeTask()
                // with the following:
                //      result = await DoSomeTask().ConfigureAwait(false)

                HttpResponseMessage response = await client.PostAsJsonAsync("", scoreRequest);
}

// 我是这样调用函数的

ServiceConnect.InvokeRequestResponseService("xyz").Wait();

这里 Wait() 返回 viod 所以我不能从这里返回任何东西。但我必须添加等待才能完成任务。谁能指导我如何获得功能响应或获得响应的其他方式。

【问题讨论】：

标签： c# async-await

【解决方案1】：

获取函数的响应，将返回类型更改为Task<HttpResponseMessage>并返回响应。

鉴于响应是唯一需要等待的东西，您可以删除 async 关键工作并返回响应任务

public static Task<HttpResponseMessage> InvokeRequestResponseService( string pstrRequest)
{
    ServiceConnect objServiceConnect = new ServiceConnect();
    using (var client = new HttpClient())
    {
        var scoreRequest = new
        {
            Inputs = new Dictionary<string, InputOutputTable>() {
                {
                    "input1",
                    new InputOutputTable()
                    {
                        ColumnNames = new string[] {"Assignment group", "Short description"},
                        Values = new string[,] {  { "", pstrRequest },  { "", "" },  }
                    }
                },
            },
            GlobalParameters = new Dictionary<string, string>()
            {
            }
        };
        const string apiKey = "Some API Key"; // Replace this with the API key for the web service
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);

        client.BaseAddress = new Uri("Some Uri");

        // WARNING: The 'await' statement below can result in a deadlock if you are calling this code from the UI thread of an ASP.Net application.
        // One way to address this would be to call ConfigureAwait(false) so that the execution does not attempt to resume on the original context.
        // For instance, replace code such as:
        //      result = await DoSomeTask()
        // with the following:
        //      result = await DoSomeTask().ConfigureAwait(false)

        return client.PostAsJsonAsync("", scoreRequest);
    }
}

这样就可以调用函数了

HttpResponseMessage response = await ServiceConnect.InvokeRequestResponseService("xyz");

【讨论】：