ByteScout Cloud API Server – Image To PDF API – VB.NET – Convert Images To PDF From Uploaded Files

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Module1.vb

      
Imports System.IO
Imports System.Net
Imports Newtonsoft.Json.Linq

' Please NOTE: In this sample we're assuming Cloud Api Server is hosted at "https://localhost". 
' If it's not then please replace this with with your hosting url.
Module Module1

 	' Source image files
	Dim ImageFiles() As String = New String() {".\image1.png", ".\image2.jpg"}
	' Destination PDF file name
	Const DestinationFile As String = ".\result.pdf"

	Sub Main()

		' Create standard .NET web client instance
		Dim webClient As WebClient = New WebClient()

		' 1. UPLOAD FILES TO CLOUD
		Dim uploadedFiles As List(Of String) = New List(Of String)()

		Try
			For Each imageFile As String In ImageFiles

				' 1a. RETRIEVE THE PRESIGNED URL TO UPLOAD THE FILE.

				' Prepare URL for `Get Presigned URL` API call
				Dim query As String = Uri.EscapeUriString(String.Format(
					"https://localhost/file/upload/get-presigned-url?contenttype=application/octet-stream&name={0}",
					Path.GetFileName(imageFile)))

				' Execute request
				Dim response As String = webClient.DownloadString(query)

				' Parse JSON response
				Dim json As JObject = JObject.Parse(response)

				If json("error").ToObject(Of Boolean) = False Then

					' Get URL to use for the file upload
					Dim uploadUrl As String = json("presignedUrl").ToString()
					' Get URL of uploaded file to use with later API calls
					Dim uploadedFileUrl As String = json("url").ToString()

					' 1b. UPLOAD THE FILE TO CLOUD.

					webClient.Headers.Add("content-type", "application/octet-stream")
					webClient.UploadFile(uploadUrl, "PUT", imageFile) ' You can use UploadData() instead if your file is byte[] or Stream

					uploadedFiles.Add(uploadedFileUrl)
				Else
					Console.WriteLine(json("message").ToString())
				End If

			Next

			If uploadedFiles.Count > 0 Then

				' 2. CREATE PDF DOCUMENT FROM UPLOADED IMAGE FILES

				' Prepare URL for `Image To PDF` API call
				Dim query As String = Uri.EscapeUriString(String.Format(
					"https://localhost/pdf/convert/from/image?name={0}&url={1}",
					Path.GetFileName(DestinationFile),
					String.Join(",", uploadedFiles)))

				' Execute request
				Dim response As String = webClient.DownloadString(query)

				' Parse JSON response
				Dim json As JObject = JObject.Parse(response)

				If json("error").ToObject(Of Boolean) = False Then

					' Get URL of generated PDF file
					Dim resultFileUrl As String = json("url").ToString()

					' Download PDF file
					webClient.DownloadFile(resultFileUrl, DestinationFile)

					Console.WriteLine("Generated PDF file saved as ""{0}"" file.", DestinationFile)

				Else
					Console.WriteLine(json("message").ToString())
				End If

			End If

		Catch ex As WebException
			Console.WriteLine(ex.ToString())
		End Try

		webClient.Dispose()


		Console.WriteLine()
		Console.WriteLine("Press any key...")
		Console.ReadKey()

	End Sub

End Module

    

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packages.config

      
<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Newtonsoft.Json" version="10.0.3" targetFramework="net40" />
</packages>
    

ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit ByteScout Cloud API Server Home Page

Explore ByteScout Cloud API Server Documentation

Explore Samples

Sign Up for ByteScout Cloud API Server Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit ByteScout Cloud API Server Home Page

Explore ByteScout Cloud API Server Documentation

Explore Samples

Sign Up for ByteScout Cloud API Server Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples