Split PDF C# API

Split multiple PDF documents into new PDFs. Use our C# PDF page splitting API to select pages from an existing PDF file and create a new document.

Why PSPDFKit API?

SOC 2 Compliant

Build the workflows you need without worrying about security. We don’t store any document data, and our API endpoints are served through encrypted connections.

Easy Integration

Get up and running in hours, not weeks. Access well-documented APIs and code samples that make integrating with your existing workflows a snap.

One Document, Endless Actions

With access to more than 30 tools, you can process one document in multiple ways by combining API actions. Convert, OCR, rotate, and watermark with one API call.

Simple and Transparent Pricing

Pay only for the number of documents you process. You won’t need to consider file size, datasets being merged, or different API actions being called.

Try It Out

This example will split your document into two documents. The first PDF will contain all pages except the last five, and the second PDF will contain the remaining five pages.

Use Your Free API Calls

Add a File

Add a PDF named document.pdf to your project folder. You can also use our sample file. The file name is case sensitive. Make sure the file name matches the file name in the sample code.

Run the Code

Copy the code and run it from the same folder you added the files to. For more information, see our language-specific getting started guides.

View the Results

Open first_half.pdf in your project folder to view the results.

curl -X POST https://api.pspdfkit.com/build \
  -H "Authorization: Bearer your_api_key_here" \
  -o first_half.pdf \
  --fail \
  -F document=@document.pdf \
  -F instructions='{
      "parts": [
        {
          "file": "document",
          "pages": {
            "end": -6
          }
        }
      ]
    }'

curl -X POST https://api.pspdfkit.com/build \
  -H "Authorization: Bearer your_api_key_here" \
  -o second_half.pdf \
  --fail \
  -F document=@document.pdf \
  -F instructions='{
      "parts": [
        {
          "file": "document",
          "pages": {
            "start": -5
          }
        }
      ]
    }'

curl -X POST https://api.pspdfkit.com/build ^
  -H "Authorization: Bearer your_api_key_here" ^
  -o first_half.pdf ^
  --fail ^
  -F document=@document.pdf ^
  -F instructions="{\"parts\": [{\"file\": \"document\", \"pages\": {\"end\": -6}}]}"

curl -X POST https://api.pspdfkit.com/build ^
  -H "Authorization: Bearer your_api_key_here" ^
  -o second_half.pdf ^
  --fail ^
  -F document=@document.pdf ^
  -F instructions="{\"parts\": [{\"file\": \"document\", \"pages\": {\"start\": -5}}]}"

package com.example.pspdfkit;

import java.io.File;
import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;

import org.json.JSONArray;
import org.json.JSONObject;

import okhttp3.MediaType;
import okhttp3.MultipartBody;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public final class PspdfkitApiExample {
  public static void main(final String[] args) throws IOException {
    final RequestBody firstHalfBody = new MultipartBody.Builder()
      .setType(MultipartBody.FORM)
      .addFormDataPart(
        "document",
        "document.pdf",
        RequestBody.create(
          new File("document.pdf"),
          MediaType.parse("application/pdf")
        )
      )
      .addFormDataPart(
        "instructions",
        new JSONObject()
          .put("parts", new JSONArray()
            .put(new JSONObject()
              .put("file", "document")
              .put("pages", new JSONObject()
                .put("end", -6)
              )
            )
          ).toString()
      )
      .build();

    final Request firstHalfRequest = new Request.Builder()
      .url("https://api.pspdfkit.com/build")
      .method("POST", firstHalfBody)
      .addHeader("Authorization", "Bearer your_api_key_here")
      .build();

    final RequestBody secondHalfBody = new MultipartBody.Builder()
      .setType(MultipartBody.FORM)
      .addFormDataPart(
        "document",
        "document.pdf",
        RequestBody.create(
          new File("document.pdf"),
          MediaType.parse("application/pdf")
        )
      )
      .addFormDataPart(
        "instructions",
        new JSONObject()
          .put("parts", new JSONArray()
            .put(new JSONObject()
              .put("file", "document")
              .put("pages", new JSONObject()
                .put("start", -5)
              )
            )
          ).toString()
      )
      .build();

    final Request secondHalfRequest = new Request.Builder()
      .url("https://api.pspdfkit.com/build")
      .method("POST", secondHalfBody)
      .addHeader("Authorization", "Bearer your_api_key_here")
      .build();

    executeRequest(firstHalfRequest, "first_half.pdf");
    executeRequest(secondHalfRequest, "second_half.pdf");
  }

  private static void executeRequest(final Request request, final String outputFileName) throws IOException {
    final OkHttpClient client = new OkHttpClient()
      .newBuilder()
      .build();

    final Response response = client.newCall(request).execute();

    if (response.isSuccessful()) {
      Files.copy(
        response.body().byteStream(),
        FileSystems.getDefault().getPath(outputFileName),
        StandardCopyOption.REPLACE_EXISTING
      );
    } else {
      // Handle the error
      throw new IOException(response.body().string());
    }
  }
}

using System;
using System.IO;
using System.Net;
using RestSharp;

namespace PspdfkitApiDemo
{
  class Program
  {
    static void Main(string[] args)
    {
      var client = new RestClient("https://api.pspdfkit.com/build");

      var firstHalfRequest = new RestRequest(Method.POST)
        .AddHeader("Authorization", "Bearer your_api_key_here")
        .AddFile("document", "document.pdf")
        .AddParameter("instructions", new JsonObject
        {
          ["parts"] = new JsonArray
          {
            new JsonObject
            {
              ["file"] = "document",
              ["pages"] = new JsonObject
              {
                ["end"] = -6
              }
            }
          }
        }.ToString());
      firstHalfRequest.AdvancedResponseWriter = OutputFileResponseWriter("first_half.pdf");

      var secondHalfRequest = new RestRequest(Method.POST)
        .AddHeader("Authorization", "Bearer your_api_key_here")
        .AddFile("document", "document.pdf")
        .AddParameter("instructions", new JsonObject
        {
          ["parts"] = new JsonArray
          {
            new JsonObject
            {
              ["file"] = "document",
              ["pages"] = new JsonObject
              {
                ["start"] = -5
              }
            }
          }
        }.ToString());
      secondHalfRequest.AdvancedResponseWriter = OutputFileResponseWriter("second_half.pdf");

      client.Execute(firstHalfRequest);
      client.Execute(secondHalfRequest);
    }

    static Action<Stream, IHttpResponse> OutputFileResponseWriter(string outputFileName)
    {
      return (responseStream, response) =>
      {
        if (response.StatusCode == HttpStatusCode.OK)
        {
          using (responseStream)
          {
            using var outputFileWriter = File.OpenWrite(outputFileName);
            responseStream.CopyTo(outputFileWriter);
          }
        }
        else
        {
          var responseStreamReader = new StreamReader(responseStream);
          Console.Write(responseStreamReader.ReadToEnd());
        }
      };
    }
  }
}

// This code requires Node.js. Do not run this code directly in a web browser.

const axios = require('axios')
const FormData = require('form-data')
const fs = require('fs')

;(async () => {
  const firstHalf = new FormData()
  firstHalf.append('instructions', JSON.stringify({
    parts: [
      {
        file: "document",
        pages: {
          end: -6
        }
      }
    ]
  }))
  firstHalf.append('document', fs.createReadStream('document.pdf'))

  const secondHalf = new FormData()
  secondHalf.append('instructions', JSON.stringify({
    parts: [
      {
        file: "document",
        pages: {
          start: -5
        }
      }
    ]
  }))
  secondHalf.append('document', fs.createReadStream('document.pdf'))

  await executeRequest(firstHalf, "first_half.pdf")
  await executeRequest(secondHalf, "second_half.pdf")
})()

async function executeRequest(formData, outputFile) {
  try {
    const response = await axios.post('https://api.pspdfkit.com/build', formData, {
      headers: formData.getHeaders({
          'Authorization': 'Bearer your_api_key_here'
      }),
      responseType: "stream"
    })

    response.data.pipe(fs.createWriteStream(outputFile))
  } catch (e) {
    const errorString = await streamToString(e.response.data)
    console.log(errorString)
  }
}

function streamToString(stream) {
  const chunks = []
  return new Promise((resolve, reject) => {
    stream.on("data", (chunk) => chunks.push(Buffer.from(chunk)))
    stream.on("error", (err) => reject(err))
    stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8")))
  })
}

import requests
import json

def process_first_half():
  instructions = {
    'parts': [
      {
        'file': 'document',
        'pages': {
          'end': -6
        }
      }
    ]
  }

  response = requests.request(
    'POST',
    'https://api.pspdfkit.com/build',
    headers = {
      'Authorization': 'Bearer your_api_key_here'
    },
    files = {
      'document': open('document.pdf', 'rb')
    },
    data = {
      'instructions': json.dumps(instructions)
    },
    stream = True
  )

  if response.ok:
    with open('first_half.pdf', 'wb') as fd:
      for chunk in response.iter_content(chunk_size=8096):
        fd.write(chunk)
  else:
    print(response.text)
    exit()

def process_second_half():
  instructions = {
    'parts': [
      {
        'file': 'document',
        'pages': {
          'start': -5
        }
      }
    ]
  }

  response = requests.request(
    'POST',
    'https://api.pspdfkit.com/build',
    headers = {
      'Authorization': 'Bearer your_api_key_here'
    },
    files = {
      'document': open('document.pdf', 'rb')
    },
    data = {
      'instructions': json.dumps(instructions)
    },
    stream = True
  )

  if response.ok:
    with open('second_half.pdf', 'wb') as fd:
      for chunk in response.iter_content(chunk_size=8096):
        fd.write(chunk)
  else:
    print(response.text)
    exit()

process_first_half()
process_second_half()

<?php

function process_first_half() {
  $FileHandle = fopen('first_half.pdf', 'w+');

  $curl = curl_init();

  $instructions = '{
    "parts": [
      {
        "file": "document",
        "pages": {
          "end": -6
        }
      }
    ]
  }';

  curl_setopt_array($curl, array(
    CURLOPT_URL => 'https://api.pspdfkit.com/build',
    CURLOPT_CUSTOMREQUEST => 'POST',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_ENCODING => '',
    CURLOPT_POSTFIELDS => array(
      'instructions' => $instructions,
      'document' => new CURLFILE('document.pdf')
    ),
    CURLOPT_HTTPHEADER => array(
      'Authorization: Bearer your_api_key_here'
    ),
    CURLOPT_FILE => $FileHandle,
  ));

  $response = curl_exec($curl);

  curl_close($curl);

  fclose($FileHandle);
}

function process_second_half() {
  $FileHandle = fopen('second_half.pdf', 'w+');

  $curl = curl_init();

  $instructions = '{
    "parts": [
      {
        "file": "document",
        "pages": {
          "start": -5
        }
      }
    ]
  }';

  curl_setopt_array($curl, array(
    CURLOPT_URL => 'https://api.pspdfkit.com/build',
    CURLOPT_CUSTOMREQUEST => 'POST',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_ENCODING => '',
    CURLOPT_POSTFIELDS => array(
      'instructions' => $instructions,
      'document' => new CURLFILE('document.pdf')
    ),
    CURLOPT_HTTPHEADER => array(
      'Authorization: Bearer your_api_key_here'
    ),
    CURLOPT_FILE => $FileHandle,
  ));

  $response = curl_exec($curl);

  curl_close($curl);

  fclose($FileHandle);
}

process_first_half();
process_second_half();

Using Postman? Download our official collection and start using the API with a single click. Read more