Xojo Plugin
Mailgun Send Send HTML Email with Attachments and HTML Images

Sends an HTML email with images and attachments.
Chilkat Xojo Plugin Downloads

Xojo Plugin
Dim success As Boolean
success = False

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Dim http As New Chilkat.Http

http.Login = "api"
http.Password = "sending_api_key"//  Replace with your actual sending API key.

Dim req As New Chilkat.HttpRequest
req.HttpVerb = "POST"
req.Path = "/v3/YOUR_DOMAIN_NAME/messages"
req.ContentType = "multipart/form-data"

// Change YOUR_DOMAIN_NAME to something like "mg.your-domain.com".
req.AddParam "from","Your Name <mailgun@YOUR_DOMAIN_NAME>"
req.AddParam "to","Joe Example <joe@example.com>"
req.AddParam "subject","Hello Joe Example"
req.AddParam "html","<html><body><b>This is the HTML body</b><br><img src=""cid:cidStarfish.jpg""></body></html>"

// An a attachd file
Dim bd As New Chilkat.BinData
success = bd.LoadFile("qa_data/hamlet.zip")
If (success = False) Then
    System.DebugLog("Failed to load file attachment.")
    Return
End If

success = req.AddBdForUpload("attachment","hamlet.zip",bd,"application/zip")

// add an image as CID
success = bd.LoadFile("qa_data/jpg/starfish.jpg")
If (success = False) Then
    System.DebugLog("Failed to load HTML image.")
    Return
End If

success = req.AddBdForUpload("inline","cidStarfish.jpg",bd,"image/jpeg")

Dim resp As New Chilkat.HttpResponse
success = http.HttpSReq("api.mailgun.net",443,True,req,resp)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

Dim sbResponseBody As New Chilkat.StringBuilder
success = resp.GetBodySb(sbResponseBody)
Dim jResp As New Chilkat.JsonObject
success = jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = False

System.DebugLog("Response Body:")
System.DebugLog(jResp.Emit())

Dim respStatusCode As Int32
respStatusCode = resp.StatusCode
System.DebugLog("Response Status Code = " + Str(respStatusCode))
If (respStatusCode >= 400) Then
    System.DebugLog("Response Header:")
    System.DebugLog(resp.Header)
    System.DebugLog("Failed.")
    Return
End If

// Sample JSON response:
// (Sample code for parsing the JSON response is shown below)

// {
//   "id": "<20210429234809.1.2D550E1C94D3D98F@sandbox0e542e4c577f4bbb98c8bf6b6bca727b.mailgun.org>",
//   "message": "Queued. Thank you."
// }

// Sample code for parsing the JSON response...
// Use the following online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON

Dim id As String
id = jResp.StringOf("id")
Dim message As String
message = jResp.StringOf("message")