C# 如何在xamarin中向HttpWebRequest添加头

req.Headers.Add（“应用程序类型”、“IOSAPP”）

我正在开发Xamarin表单应用程序，希望从我的webapi获取数据。当我键入
request.Headers.Add
时，我在Add上看到了一条带此消息的粗线条

“/Users/etgmacmini3/Projects/sample1/sample1/GlobalClass.cs（16,16）：错误CS1061:'WebHeaderCollection'不包含'Add'的定义，并且找不到接受'WebHeaderCollection'类型的第一个参数的扩展方法'Add'（是否缺少using指令或程序集引用？）（CS1061）（sample1）”

不确定您的“req”对象是什么类型，但如果您遵循这一点，它应该可以帮助您向Web API发送HTTP请求：

using System.Net;
using System.Net.Http;

var httpClient = new HttpClient();
var data = "Some JSON data to be sent in your request body"; //May not need this, based on your app needs
var contentType = "application/json"; //May vary based on your app
var httpMethod = HttpMethod.Post; //or Get, or whatever HTTP verb your API endpoint needs

var request = new HttpRequestMessage()
{
    RequestUri = new Uri("http://YourWebApiUrlHere"),
    Method = httpMethod,  
    Content = new StringContent(data, System.Text.Encoding.UTF8, contentType) 
};
request.Headers.Add("YourHeaderName", "YourHeaderValue");

var httpResponse = await httpClient.SendAsync(request);

if (httpResponse.StatusCode == HttpStatusCode.OK)
{
    //It worked, so do something
}
else
{
    //It didn't work, so do something else
}

@萨提斯帮了忙吗？