Convert Word document to Image in Azure Functions v4

13 Jun 20246 minutes to read

Syncfusion DocIO is a .NET Core Word library used to create, read, edit, and convert Word documents programmatically without Microsoft Word or interop dependencies. Using this library, you can convert a Word document to image in Azure Functions v4.

Steps to convert a Word document to Image in Azure Functions v4

Step 1: Create a new Azure Functions project.

Step 2: Create a project name and select the location.

Step 3: Select function worker as .NET 6.0(Long-term support).

Step 4: Install the Syncfusion.DocIORenderer.Net.Core NuGet package as a reference to your project from NuGet.org.

NOTE

Starting with v16.2.0.x, if you reference Syncfusion assemblies from trial setup or from the NuGet feed, you also have to add “Syncfusion.Licensing” assembly reference and include a license key in your projects. Please refer to this link to know about registering Syncfusion license key in your application to use our components.

Step 5: Include the following namespaces in the Function1.cs file.

C#

using Syncfusion.DocIO;
using Syncfusion.DocIO.DLS;
using Syncfusion.DocIORenderer;

Step 6: Add the following code snippet in Run method of Function1 class to perform convert Word to image in Azure Functions and return the resultant image to client end.

C#

//Gets the input Word document as stream from request
Stream stream = req.Content.ReadAsStreamAsync().Result;
//Loads an existing Word document
using (WordDocument document = new WordDocument(stream, FormatType.Docx))
{
    //Creates an instance of the DocIORenderer
    using (DocIORenderer render = new DocIORenderer())
    {
        Stream imageStream = document.RenderAsImages(0, ExportImageFormat.Jpeg);
        //Reset the stream position.
        imageStream.Position = 0;
        MemoryStream memoryStream = new MemoryStream();
        //Saves the image file 
        imageStream.CopyTo(memoryStream);
        //Reset the memory stream position
        memoryStream.Position = 0;
        //Create the response to return
        HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
        //Set the Word document saved stream as content of response
        response.Content = new ByteArrayContent(memoryStream.ToArray());
        //Set the contentDisposition as attachment
        response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
        {
            FileName = "WordToImage.Jpeg"
        };
        //Set the content type as Word document mime type
        response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/jpeg");
        //Return the response with output Word document stream
        return response;
    }
}

Step 7: Right click the project and select Publish. Then, create a new profile in the Publish Window.

Step 8: Select the target as Azure and click Next button.

Step 9: Select the Create new button.

Step 10: Click Create button.

Step 11: After creating app service then click Finish button.

Step 12: Click the Publish button.

Step 13: Publish has been succeed.

Step 14: Now, go to Azure portal and select the App Services. After running the service, click Get function URL by copying it. Then, paste it in the below client sample (which will request the Azure Functions, to perform Word to image conversion using the template Word document). You will get the output image as follows.

Steps to post the request to Azure Functions

Step 1: Create a console application to request the Azure Functions API.

Step 2: Add the following code snippet into Main method to post the request to Azure Functions with template Word document and get the resultant image document.

C#

//Reads the template Word document.
FileStream fs = new FileStream("Input.docx", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
fs.Position = 0;
//Saves the Word document in memory stream.
MemoryStream inputStream = new MemoryStream();
fs.CopyTo(inputStream);
inputStream.Position = 0;
try
{
    Console.WriteLine("Please enter your Azure Functions URL :");
    string functionURL = Console.ReadLine();
    //Create HttpWebRequest with hosted azure functions URL.                
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(functionURL);
    //Set request method as POST
    req.Method = "POST";
    //Get the request stream to save the Word document stream
    Stream stream = req.GetRequestStream();
    //Write the Word document stream into request stream
    stream.Write(inputStream.ToArray(), 0, inputStream.ToArray().Length);
    //Gets the responce from the Azure Functions.
    HttpWebResponse res = (HttpWebResponse)req.GetResponse();
    //Saves the image stream.
    FileStream fileStream = File.Create("WordToImage.Jpeg");
    res.GetResponseStream().CopyTo(fileStream);
    //Dispose the streams
    inputStream.Dispose();
    fileStream.Dispose();
}
catch (Exception ex)
{
    throw;
}

From GitHub, you can download the console application and Azure Functions v4.

Click here to explore the rich set of Syncfusion Word library (DocIO) features.

An online sample link to convert Word document to image in ASP.NET Core.