Conversion error: Could not open url. Select.HtmlToPdf.NetCore

I am evaluating Select.HtmlToPdf.NetCore to convert Html string to Pdf in my C# Azure function app.

I was trying SelectPdf-HtmlToPdf-Samples-v23.2.0 downloaded from Selectpdf website especially the Azure function.

I tried invoking the Azure function running from a local Visual Studio instance but getting an error upon executing;

doc = converter.ConvertHtmlString(html);

I am not using a base url here but I am getting the error

Conversion error: Could not open url.

Since I am not using a base url as a parameter, not sure what is causing this error.

Solution

Conversion error: Could not open url. Select.HtmlToPdf.NetCore

Below code works fine for me:

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Extensions.Logging;
using SelectPdf;

namespace FunctionApp121
{
    public class Function1
    {
        private readonly ILogger<Function1> _logger;
        public Function1(ILogger<Function1> logger)
        {
            _logger = logger;
        }
        [Function("Function1")]
        public IActionResult Run([HttpTrigger(AuthorizationLevel.Function, "get", "post")] HttpRequest req)
        {
            _logger.LogInformation("Hello Rithwik, C# Code has started executing");
            PdfDocument testrith = new PdfDocument();
            HtmlToPdf converith = new HtmlToPdf();
            string testhtml = "<html><body>Hello Rithwik Bojja!</body></html>";
            testrith = converith.ConvertHtmlString(testhtml);
            MemoryStream rithpdf = new MemoryStream();
            testrith.Save(rithpdf);
            testrith.Close();
            rithpdf.Seek(0, SeekOrigin.Begin);
            _logger.LogInformation("Hello Rithwik,Execution Completed");
            return new FileStreamResult(rithpdf, "application/pdf")
            {
                FileDownloadName = "rithwiktest.pdf"
            };
        }
    }
}

csproj:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <AzureFunctionsVersion>v4</AzureFunctionsVersion>
    <OutputType>Exe</OutputType>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
  <ItemGroup>
    <FrameworkReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.20.1" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.1.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http.AspNetCore" Version="1.2.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.16.4" />
    <PackageReference Include="Microsoft.ApplicationInsights.WorkerService" Version="2.21.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.ApplicationInsights" Version="1.1.0" />
    <PackageReference Include="Select.HtmlToPdf" Version="23.2.0" />
    <PackageReference Include="Select.HtmlToPdf.NetCore" Version="23.1.0" />
  </ItemGroup>
  <ItemGroup>
    <None Update="host.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
    </None>
    <None Update="local.settings.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
      <CopyToPublishDirectory>Never</CopyToPublishDirectory>
    </None>
  </ItemGroup>
  <ItemGroup>
    <Using Include="System.Threading.ExecutionContext" Alias="ExecutionContext" />
  </ItemGroup>
</Project>

Output:

enter image description here

Alternatively, html sent as body when calling function:

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Extensions.Logging;
using SelectPdf;

namespace FunctionApp121
{
    public class Function1
    {
        private readonly ILogger<Function1> _logger;
        public Function1(ILogger<Function1> logger)
        {
            _logger = logger;
        }
        [Function("Function1")]
        public async Task<IActionResult> RunAsync([HttpTrigger(AuthorizationLevel.Function, "get", "post")] HttpRequest req)
        {
            _logger.LogInformation("Hello Rithwik, C# Code has started executing");
            string testhtml = await new StreamReader(req.Body).ReadToEndAsync();

            if (string.IsNullOrEmpty(testhtml))
            {
                return new BadRequestObjectResult("Please provide HTML content in the request body.");
            }
            PdfDocument testrith = new PdfDocument();
            HtmlToPdf converith = new HtmlToPdf();
            testrith = converith.ConvertHtmlString(testhtml);
            MemoryStream rithpdf = new MemoryStream();
            testrith.Save(rithpdf);
            testrith.Close();
            rithpdf.Seek(0, SeekOrigin.Begin);
            _logger.LogInformation("Hello Rithwik,Execution Completed");
            return new FileStreamResult(rithpdf, "application/pdf")
            {
                FileDownloadName = "rithwiktest.pdf"
            };
        }
    }
}

Output:

enter image description here