POST request using WWW class with header

I am trying to make a POST request to restful web APIs in Unity.

The header would be Content-Type: application/json

An example of the raw data input is, where data is the key and json string is the value:

{“data”:{“username":“name”,“email”:"email@gmail.com”,“age_range”:21,“gender”:“male”,“location”:“california”}}

Here’s my script:

private static readonly string POSTAddUserURL = "http://db.url.com/api/addUser";

public WWW POST()
{
    WWW www;

    Hashtable postHeader = new Hashtable();
    postHeader.Add("Content-Type", "application/json");

    WWWForm form = new WWWForm();
    form.AddField("data", jsonStr);
    www = new WWW(POSTAddUserURL, form);

    StartCoroutine(WaitForRequest(www));
    return www;
}

IEnumerator WaitForRequest(WWW data)
{
    yield return data; // Wait until the download is done

    if (data.error != null)
    {
        MainUI.ShowDebug("There was an error sending request: " + data.error);
    }
    else
    {
        MainUI.ShowDebug("WWW Request: " + data.text);
    }
}

How do I send the request using WWW class with both form and header? Or, just in general, how to i send this kind of post request?

Just call WWW with a third parameter, which would be your Header . Like this :

www = new WWW(POSTAddUserURL, form, postHeader);

Watch this video to solve :Post data to a URL Unity - YouTube