Link Search Menu Expand Document

PDF Text Search from Uploaded File Asynchronously - C#

PDF Search Text sample in C# demonstrating ‘PDF Text Search from Uploaded File Asynchronously’

Program.cs
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Threading;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace ByteScoutWebApiExample
{
    class Program
    {
        // The authentication key (API Key).
        // Get your own by registering at https://app.pdf.co
        const String API_KEY = "*****************************************";

        // Source PDF file
        const string SourceFile = @".\sample.pdf";

        // Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'.
        const string Pages = "";

        // PDF document password. Leave empty for unprotected documents.
        const string Password = "";

        // Search string. 
        const string SearchString = @"\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 bool RegexSearch = true;

        // (!) Make asynchronous job
        const bool Async = true;

        static void Main(string[] args)
        {
            // Create standard .NET web client instance
            WebClient 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
            string query = 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
                string response = webClient.DownloadString(query);

                // Parse JSON response
                JObject json = JObject.Parse(response);

                if (json["error"].ToObject<bool>() == false)
                {
                    // Get URL to use for the file upload
                    string uploadUrl = json["presignedUrl"].ToString();
                    string uploadedFileUrl = 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[] or Stream

                    // 3. MAKE UPLOADED PDF FILE SEARCHABLE

                    // URL for `PDF Text Search` API call
                    // See documentation: https://apidocs.pdf.co
                    var url = "https://api.pdf.co/v1/pdf/find";

                    // Prepare requests params as JSON
                    Dictionary<string, object> parameters = new Dictionary<string, object>();
                    parameters.Add("password", Password);
                    parameters.Add("pages", Pages);
                    parameters.Add("url", uploadedFileUrl);
                    parameters.Add("searchString", SearchString);
                    parameters.Add("regexSearch", RegexSearch);
                    parameters.Add("async", Async);

                    // Convert dictionary of params to JSON
                    string jsonPayload = JsonConvert.SerializeObject(parameters);

                    // Execute POST request with JSON payload
                    response = webClient.UploadString(url, jsonPayload);

                    // Parse JSON response
                    json = JObject.Parse(response);

                    if (json["error"].ToObject<bool>() == false)
                    {
                        // Asynchronous job ID
                        string jobId = json["jobId"].ToString();

                        // URL of generated json file that will available after the job completion
                        string 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
                        {
                            string status = CheckJobStatus(jobId); // Possible statuses: "working", "failed", "aborted", "success".

                            // Display timestamp and status (for demo purposes)
                            Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status);

                            if (status == "success")
                            {
                                // Execute request
                                string respFileJson = webClient.DownloadString(resultFileUrl);

                                // Parse JSON response
                                JArray jsonFoundInformation = JArray.Parse(respFileJson);

                                // Display found information in console
                                foreach (JToken item in jsonFoundInformation)
                                {
                                    Console.WriteLine($"Found text \"{item["text"]}\" at coordinates {item["left"]}, {item["top"]}");
                                }

                                break;
                            }
                            else if (status == "working")
                            {
                                // Pause for a few seconds
                                Thread.Sleep(3000);
                            }
                            else
                            {
                                Console.WriteLine(status);
                                break;
                            }
                        }
                        while (true);
                    }
                    else
                    {
                        Console.WriteLine(json["message"].ToString());
                    }
                }
                else
                {
                    Console.WriteLine(json["message"].ToString());
                }
            }
            catch (WebException ex)
            {
                Console.WriteLine(ex.ToString());
            }

            webClient.Dispose();

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


        static string CheckJobStatus(string jobId)
        {
            using (WebClient webClient = new WebClient())
            {
                // Set API Key
                webClient.Headers.Add("x-api-key", API_KEY);

                string url = "https://api.pdf.co/v1/job/check?jobid=" + jobId;

                string response = webClient.DownloadString(url);
                JObject json = JObject.Parse(response);

                return Convert.ToString(json["status"]);
            }
        }

    }
}

PDF.co Web API: the Web API with a set of tools for documents manipulation, data conversion, data extraction, splitting and merging of documents. Includes image recognition, built-in OCR, barcode generation and barcode decoders to decode bar codes from scans, pictures and pdf.

Get your PDF.co API key here!

Download Source Code (.zip)

return to the previous page explore PDF Search Text endpoint