(VB.NET) Outlook Send HTML Email with Embedded Images and Attachments

This example sends an HTML email with both embedded images and attachments. Other examples exist for:

Sending plain-text email.
Sending HTML email.
Sending HTML email with embedded images.
Sending plain-text email with attachments.

Chilkat .NET Downloads

Chilkat .NET Framework

Chilkat for .NET Core

' Important: This example requires Chilkat v9.5.0.68 or greater.

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

Dim http As New Chilkat.Http

' Use your previously obtained access token here:
' See the following examples for getting an access token:
'    Get Microsoft Graph OAuth2 Access Token (Azure AD v2.0 Endpoint).
'    Get Microsoft Graph OAuth2 Access Token (Azure AD Endpoint).
'    Refresh Access Token (Azure AD v2.0 Endpoint).
'    Refresh Access Token (Azure AD Endpoint).

http.AuthToken = "MICROSOFT_GRAPH_ACCESS_TOKEN"

' To send mail, we'll POST to the following endpoint:
' 
' POST /users/{id | userPrincipalName}/sendMail
' 
' (The special keyword "me" may be used in place of a principal name.)
' 

' This example will send HTML email containing the following HTML body.
' After the 

' 	<html>
' 	<head>
' 	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
' 	<meta content="text/html; charset=utf-8">
' 	</head>
' 	<body bgcolor="#FFFFFF">
' 	<font face="Calibri">This is a test <b>HTML email with embedded images</b>.<br>
' 	<br>
' 	<img alt="" src="cid:starfish"><br>
' 	<img alt="" src="cid:hedgehogs"><br>
' 	</font>
' 	</body>
' 	</html>

' Build the HTML body...
Dim bCrlf As Boolean = True
Dim sbHtmlBody As New Chilkat.StringBuilder
sbHtmlBody.AppendLine("<html>",bCrlf)
sbHtmlBody.AppendLine("<head>",bCrlf)
sbHtmlBody.AppendLine("<meta http-equiv=""Content-Type"" content=""text/html; charset=utf-8"">",bCrlf)
sbHtmlBody.AppendLine("<meta content=""text/html; charset=utf-8"">",bCrlf)
sbHtmlBody.AppendLine("</head>",bCrlf)
sbHtmlBody.AppendLine("<body bgcolor=""#FFFFFF"">",bCrlf)
sbHtmlBody.AppendLine("<font face=""Calibri"">This is a test <b>HTML email with embedded images</b>.<br>",bCrlf)
sbHtmlBody.AppendLine("<br>",bCrlf)
sbHtmlBody.AppendLine("<img alt="""" src=""cid:starfish""><br>",bCrlf)
sbHtmlBody.AppendLine("<img alt="""" src=""cid:hedgehogs""><br>",bCrlf)
sbHtmlBody.AppendLine("</font>",bCrlf)
sbHtmlBody.AppendLine("</body>",bCrlf)
sbHtmlBody.AppendLine("</html>",bCrlf)

' Load the embedded image files.
Dim jpgStarfish As New Chilkat.BinData
jpgStarfish.LoadFile("qa_data/jpg/starfish.jpg")
Dim jpgHedgeHogs As New Chilkat.BinData
jpgHedgeHogs.LoadFile("qa_data/jpg/hedgehogs.jpg")

' Load files that are to be attached (not inline images)
Dim attach1 As New Chilkat.BinData
attach1.LoadFile("qa_data/pdf/fishing.pdf")
Dim attach2 As New Chilkat.BinData
attach2.LoadFile("qa_data/msword/sample.docx")

' The body of the POST request contains JSON that specifies the email subject, body,
' recipients, etc.  This example will build the following JSON HTML email with
' two embedded images and two attachments.
' 
' The only difference between an embedded inline image and an attachment is that the
' inline image must have a cid that corresponds to the "cid:" found in the "src" attribute
' of an IMG tag within the HTML body of the email.  (The inline image is also marked as "isInline",
' whereas the attachments are not, but I don't know if this actually makes a difference..)
' 

' 	{
' 	  "message": {
' 	    "subject": "Sample HTML Email with Embedded Images and Attachments",
' 	    "body": {
' 	      "contentType": "html",
' 	      "content": "The HTML body goes here..."
' 	    },
' 	    "toRecipients": [
' 	      {
' 	        "emailAddress": {
' 		  "name": "Chilkat Software",
' 	          "address": "admin@chilkat.io"
' 	        }
' 	      },
' 	      {
' 	        "emailAddress": {
' 	          "address": "chilkat.support@gmail.com"
' 	        }
' 	      }
' 	    ],
' 	    "ccRecipients": [
' 	      {
' 	        "emailAddress": {
' 		  "name": "Chilkat Blog",
' 		  "address": "admin@cknotes.com"
' 	        }
' 	      }
' 	    ],
' 	    "attachments": [
' 	       {
' 	         "@odata.type": "#microsoft.graph.fileAttachment",
' 	         "name": "starfish.jpg",
' 	         "contentType": "image/jpeg",
' 	         "size": 6497,
' 	         "isInline": true,
' 	         "contentId": "starfish",
' 	         "contentLocation": null,
' 	         "contentBytes": "base64_data_here"
' 	       },
' 	       {
' 	         "@odata.type": "#microsoft.graph.fileAttachment",
' 	         "name": "hedgehogs.jpg",
' 	         "contentType": "image/jpeg",
' 	         "size": 48845,
' 	         "isInline": true,
' 	         "contentId": "hedgehogs",
' 	         "contentLocation": null,
' 	         "contentBytes": "base64_data_here"
' 	       },
' 	       {
' 	         "@odata.type": "#microsoft.graph.fileAttachment",
' 	         "name": "fishing.pdf",
' 	         "contentType": "application/pdf",
' 	         "size": <theActualSize>,
' 	         "isInline": false,
' 	         "contentBytes": "base64_data_here"
' 	       },
' 	       {
' 	         "@odata.type": "#microsoft.graph.fileAttachment",
' 	         "name": "sample.docx",
' 	         "contentType": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
' 	         "size": <theActualSize>,
' 	         "isInline": false,
' 	         "contentBytes": "base64_data_here"
' 	       }
' 	    ]
' 	  },
' 	  "saveToSentItems": true
' 	}
' 
' Build the above JSON.
Dim json As New Chilkat.JsonObject
json.UpdateString("message.subject","Sample HTML Email with Embedded Images and Attachments")
json.UpdateString("message.body.contentType","html")
json.UpdateString("message.body.content",sbHtmlBody.GetAsString())

json.UpdateString("message.toRecipients[0].emailAddress.name","Chilkat Software")
json.UpdateString("message.toRecipients[0].emailAddress.address","admin@chilkat.io")
json.UpdateString("message.toRecipients[1].emailAddress.address","chilkat.support@gmail.com")
json.UpdateString("message.ccRecipients[0].emailAddress.name","Chilkat Blog")
json.UpdateString("message.ccRecipients[0].emailAddress.address","admin@cknotes.com")

json.UpdateString("message.attachments[0].""@odata.type""","#microsoft.graph.fileAttachment")
json.UpdateString("message.attachments[0].name","starfish.jpg")
json.UpdateString("message.attachments[0].contentType","image/jpeg")
json.UpdateInt("message.attachments[0].size",jpgStarfish.NumBytes)
json.UpdateBool("message.attachments[0].isInline",True)
' This contentId must match the "cid:" in the HTML
json.UpdateString("message.attachments[0].contentId","starfish")
json.UpdateNull("message.attachments[0].contentLocation")
json.UpdateBd("message.attachments[0].contentBytes","base64",jpgStarfish)

json.UpdateString("message.attachments[1].""@odata.type""","#microsoft.graph.fileAttachment")
json.UpdateString("message.attachments[1].name","hedgehogs.jpg")
json.UpdateString("message.attachments[1].contentType","image/jpeg")
json.UpdateInt("message.attachments[1].size",jpgHedgeHogs.NumBytes)
json.UpdateBool("message.attachments[1].isInline",True)
' This contentId must match the "cid:" in the HTML
json.UpdateString("message.attachments[1].contentId","hedgehogs")
json.UpdateNull("message.attachments[1].contentLocation")
json.UpdateBd("message.attachments[1].contentBytes","base64",jpgHedgeHogs)

json.UpdateString("message.attachments[2].""@odata.type""","#microsoft.graph.fileAttachment")
json.UpdateString("message.attachments[2].name","fishing.pdf")
json.UpdateString("message.attachments[2].contentType","application/pdf")
json.UpdateInt("message.attachments[2].size",attach1.NumBytes)
json.UpdateBool("message.attachments[2].isInline",False)
json.UpdateBd("message.attachments[2].contentBytes","base64",attach1)

json.UpdateString("message.attachments[3].""@odata.type""","#microsoft.graph.fileAttachment")
json.UpdateString("message.attachments[3].name","sample.docx")
json.UpdateString("message.attachments[3].contentType","application/vnd.openxmlformats-officedocument.wordprocessingml.document")
json.UpdateInt("message.attachments[3].size",attach2.NumBytes)
json.UpdateBool("message.attachments[3].isInline",False)
json.UpdateBd("message.attachments[3].contentBytes","base64",attach2)

json.UpdateBool("saveToSentItems",True)

' -------------------------------------------------------------
' Important: This example requires Chilkat v9.5.0.68 or greater.
' -------------------------------------------------------------

' Send the HTTP POST (i.e. send the HTML email)
Dim resp As Chilkat.HttpResponse = http.PostJson3("https://graph.microsoft.com/v1.0/me/sendMail","application/json",json)
If (http.LastMethodSuccess <> True) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If


' The send succeeded if the response status code = 202.
' In the success case, there is no response body.  (We just get the response code to know that it succeeded.)
If (resp.StatusCode <> 202) Then
    json.Load(resp.BodyStr)
    json.EmitCompact = False
    Debug.WriteLine(json.Emit())
    Debug.WriteLine("Failed, response status code = " & resp.StatusCode)
Else
    Debug.WriteLine("Outlook HTML Mail Sent.")
End If