C# 如何从Asp.net MVC中的API获取PDF文件？

我想从ASP.NETCore中的API获取一个pdf文件，但我不知道怎么做。 我所做的是向api发送一个模型，然后收到一个pdf文件

这是我的API中返回文件的方法（在Postman中是有效的）

这是我在web应用程序中的代码，但它不起作用

    [HttpGet]
    public FileResult getPDF(int factura) 
    {

        this.GetSession();      

        // Object sent to the web api

        FacturaRequest oFacturaRequest = new FacturaRequest();
        oFacturaRequest.Token = oUserSession.accessToken;
        oFacturaRequest.IdFactura = factura;

        RequestUtil oRequestUtil = new RequestUtil();


        JavaScriptSerializer js = new JavaScriptSerializer();   
        string json = JsonConvert.SerializeObject(oFacturaRequest); // Convert model to json format

        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Constants.Url.GETFACTURA);
        request.Method = "POST";
        request.PreAuthenticate = false;
        request.Accept = "application/json";
        request.MediaType = "application/json";
        request.ContentType = "application/json; charset=utf-8";
        request.Timeout = 60000;

        using (var oStreamWriter = new StreamWriter(request.GetRequestStream()))
        {
            oStreamWriter.Write(json);
            oStreamWriter.Flush();
        }

        HttpWebResponse oHttpResponse = (HttpWebResponse)request.GetResponse();
        var result = "";

        using (var oStreamReader = new StreamReader(oHttpResponse.GetResponseStream()))
        {
            result = oStreamReader.ReadToEnd();
        }

        return File(result,"application/pdf","Factura");
    }

---

是否要创建一个pdf文件，其内容基于从“Factura”web请求返回给您的JSON内容？如果我理解正确，您将需要使用收到的JSON内容从头开始构建pdf文件。一个免费的库，可以帮助您使用此itextpdf7。这里有一个链接到官方网站上的一个示例-不，我想要的是接收来自API的pdf。您想创建一个pdf文件，其内容基于从“Factura”web请求返回给您的JSON内容吗？如果我理解正确，您将需要使用收到的JSON内容从头开始构建pdf文件。一个免费的库，可以帮助您使用此itextpdf7。这里有一个链接到官方网站上的一个示例-不，我想要的是接收来自api的pdf

    [HttpGet]
    public FileResult getPDF(int factura) 
    {

        this.GetSession();      

        // Object sent to the web api

        FacturaRequest oFacturaRequest = new FacturaRequest();
        oFacturaRequest.Token = oUserSession.accessToken;
        oFacturaRequest.IdFactura = factura;

        RequestUtil oRequestUtil = new RequestUtil();


        JavaScriptSerializer js = new JavaScriptSerializer();   
        string json = JsonConvert.SerializeObject(oFacturaRequest); // Convert model to json format

        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Constants.Url.GETFACTURA);
        request.Method = "POST";
        request.PreAuthenticate = false;
        request.Accept = "application/json";
        request.MediaType = "application/json";
        request.ContentType = "application/json; charset=utf-8";
        request.Timeout = 60000;

        using (var oStreamWriter = new StreamWriter(request.GetRequestStream()))
        {
            oStreamWriter.Write(json);
            oStreamWriter.Flush();
        }

        HttpWebResponse oHttpResponse = (HttpWebResponse)request.GetResponse();
        var result = "";

        using (var oStreamReader = new StreamReader(oHttpResponse.GetResponseStream()))
        {
            result = oStreamReader.ReadToEnd();
        }

        return File(result,"application/pdf","Factura");
    }