How to Pass a Large String to a Web API Method (Apart from the URI)

Passing S.O.U.S. "Under the Table" to a Web API Method

Once you know how, it's easy to pass a S.O.U.S. (String Of Unusual Size - see the movie "The Princess Bride" if you don't understand that) to a Web API method. Here's how:

CLIENT Code

private void button1_Click(object sender, EventArgs e)
{
    ProcessRESTPostXMLFileAsStr
    ("http://Platypus:28642/api/Platypi/PostArgsAndXMLFileAsStr?serialNum=192837465&siteNum=42");
}

private void ProcessRESTPostXMLFileAsStr(string uri)
{
    using (var client = new WebClient())
    {
        client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
        StringBuilder sb = new StringBuilder();
        using (StreamReader sr = new StreamReader(@"C:\Platypus\eXtraneousMothLepidoptera.XML"))
        {
            String line;
            while ((line = sr.ReadLine()) != null)
            {
                sb.AppendLine(line);
            }
        }
        // I don't know why the prepended equals sign is necessary, but it is
        string allLines = "=" + sb.ToString();
        var result = client.UploadString(uri, "POST", allLines);
    }            
}

Obviously (hopefully), you need to replace the IP Address, Port, Controller name, and arg vals in the ProcessRESTPostXMLFileAsStr() arg, also the location of the file to read in that method.

Here, Now, is the SERVER (Web API App) Code

[Route("api/Platypi/PostArgsAndXMLFileAsStr")]
public void PostArgsAndXMLFileAsStr([FromBody] string value, string serialNum, string siteNum)
{
    string s = string.Format("{0}{1}{2}", value, serialNum, siteNum);
    // Parsing the contents of the stringified XML left as an exercise to the exorcist
}

You're Welcome

If you like this tip, respond with "as you wish" the next time your parent, child, spouse, or significant duckbilled platypus requests something of you. Again, see the aforelinked flick if your grokMeter is ululating.