How to PDF text search API in VB.NET and PDF.co Web API

How to PDF text search API in VB.NET

The sample shows steps and algorithm of how to PDF text search API and how to make it work in your VB.NET application. PDF.co Web API is the Rest API that provides set of data extraction functions, tools for documents manipulation, splitting and merging of pdf files. Includes built-in OCR, images recognition, can generate and read barcodes from images, scans and pdf and you can use it to PDF text search API with VB.NET.

The SDK samples like this one below explain how to quickly make your application do PDF text search API in VB.NET with the help of PDF.co Web API. In order to implement the functionality, you should copy and paste this code for VB.NET below into your code editor with your app, compile and run your application. Further enhancement of the code will make it more vigorous.

Trial version of PDF.co Web API is available for free. Source code samples are included to help you with your VB.NET app.

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Module1.vb
      
Imports System.IO Imports System.Net Imports System.Threading Imports Newtonsoft.Json.Linq Module Module1 ' The authentication key (API Key). ' Get your own by registering at https://app.pdf.co/documentation/api Const API_KEY As String = "***********************************" ' Source PDF file Const SourceFile As String = ".\sample.pdf" ' Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'. Const Pages As String = "" ' PDF document password. Leave empty for unprotected documents. Const Password As String = "" ' Search string. Const SearchString As String = "\d{1,}\.\d\d" 'Regular expression To find numbers Like '100.00' ' Note: Do Not use `+` char in regex, but use `{1,}` instead. ' `+` char Is valid for URL And will Not be escaped, And it will become a space char on the server side. ' Enable regular expressions (Regex) Const RegexSearch As Boolean = True ' (!) Make asynchronous job Const Async As Boolean = True Sub Main() ' Create standard .NET web client instance Dim webClient As WebClient = New WebClient() ' Set API Key webClient.Headers.Add("x-api-key", API_KEY) ' 1. RETRIEVE THE PRESIGNED URL TO UPLOAD THE FILE. ' * If you already have a direct file URL, skip to the step 3. ' Prepare URL for `Get Presigned URL` API call Dim query As String = Uri.EscapeUriString(String.Format( "https://api.pdf.co/v1/file/upload/get-presigned-url?contenttype=application/octet-stream&name={0}", Path.GetFileName(SourceFile))) Try ' 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() ' 2. UPLOAD THE FILE TO CLOUD. webClient.Headers.Add("content-type", "application/octet-stream") webClient.UploadFile(uploadUrl, "PUT", SourceFile) ' You can use UploadData() instead if your file is byte array or Stream ' 3. MAKE UPLOADED PDF FILE SEARCHABLE ' Prepare URL for PDF text search API call. ' See documentation: https : //app.pdf.co/documentation/api/1.0/pdf/find.html query = Uri.EscapeUriString( String.Format("https://api.pdf.co/v1/pdf/find?password={0}&pages={1}&url={2}&searchString={3}&regexSearch={4}&async={5}", Password, Pages, uploadedFileUrl, SearchString, RegexSearch, Async)) ' Execute request response = webClient.DownloadString(query) ' Parse JSON response json = JObject.Parse(response) If json("error").ToObject(Of Boolean) = False Then ' Asynchronous job ID Dim jobId = json("jobId").ToString() ' URL of generated json file that will available after the job completion Dim resultFileUrl = json("url").ToString() ' Check the job status in a loop. ' If you don't want to pause the main thread you can rework the code ' to use a separate thread for the status checking And completion. Do Dim status = CheckJobStatus(jobId) ' Possible statuses: "working", "failed", "aborted", "success". ' Display timestamp and status (for demo purpose) Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status) If (status = "success") Then ' Execute request Dim respFileJson As String = webClient.DownloadString(resultFileUrl) ' Parse JSON response Dim jsonFoundInformation As JArray = JArray.Parse(respFileJson) ' Display found information in console For Each item As JToken In jsonFoundInformation Console.WriteLine({code}quot;Found text {item("text")} at coordinates {item("left")}, {item("top")}") Next Exit Do ElseIf (status = "working") Then ' Pause for a few seconds Thread.Sleep(3000) Else Console.WriteLine(status) Exit Do End If Loop 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 Function CheckJobStatus(ByVal jobId As String) Using webClient As New WebClient ' Set API Key webClient.Headers.Add("x-api-key", API_KEY) Dim url As String = "https://api.pdf.co/v1/job/check?jobid=" & jobId Dim response As String = webClient.DownloadString(url) Dim json As JObject = JObject.Parse(response) Return Convert.ToString(json("status")) End Using End Function 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 PDF.co Web API Home Page

Explore PDF.co Web API Documentation

Explore Samples

Sign Up for PDF.co Web API Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

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ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit PDF.co Web API Home Page

Explore PDF.co Web API Documentation

Explore Samples

Sign Up for PDF.co Web API Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

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