Developing a C# Function Using .NET Core CLI

C# supports JSON serialization and deserialization interfaces and provides the HC.Serverless.Function.Common.JsonSerializer.dll file.

The interfaces are as follows:

T Deserialize<T>(Stream ins): Deserializes data into objects of function programs.

Stream Serialize<T>(T value): Serializes data to the returned response payload.

The following shows how to create a project named test based on .NET Core 6.0. The procedure is similar for other versions. The .NET SDK has been installed in the execution environment.

Creating a Project

Run the following command to create the /tmp/csharp/projects /tmp/csharp/release directory:
```
mkdir -p  /tmp/csharp/projects;mkdir -p  /tmp/csharp/release
```
Run the following command to go to the /tmp/csharp/projects/ directory:
```
cd /tmp/csharp/projects/
```

Create the project file test.csproj with the following content:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <RootNamespace>test</RootNamespace>
    <AssemblyName>test</AssemblyName>
  </PropertyGroup>
  <ItemGroup>
    <Reference Include="HC.Serverless.Function.Common">
      <HintPath>HC.Serverless.Function.Common.dll</HintPath>
    </Reference>
    <Reference Include="HC.Serverless.Function.Common.JsonSerializer">
      <HintPath> HC.Serverless.Function.Common.JsonSerializer.dll</HintPath>
    </Reference>
  </ItemGroup>
</Project>

Generating a Code Library

Download the dll files.
Upload the HC.Serverless.Function.Common.dll, HC.Serverless.Function.Common.JsonSerializer.dll, and Newtonsoft.Json.dll files in the package to the /tmp/csharp/projects/ directory.

Create the Class1.cs file in the /tmp/csharp/projects/ directory. The code is as follows:

      
       
         
         
           using HC.Serverless.Function.Common;
using System;
using System.IO;

namespace test
{
    public class Class1
    {
        public Stream ContextHandlerSerializer(Stream input, IFunctionContext context)
        {
            var logger = context.Logger;
            logger.Logf("CSharp runtime test(v1.0.2)");
            JsonSerializer test = new JsonSerializer();
            TestJson Testjson = test.Deserialize<TestJson>(input);
            if (Testjson != null)
            {
                logger.Logf("json Deserialize KetTest={0}", Testjson.KetTest);

            }
            else
            {
                return null;
            }

          return test.Serialize<TestJson>(Testjson);
        }

        public class TestJson
        {
            public string KetTest { get; set; }//Define the attribute of the serialization class as KetTest.

        }
    }
}

          

        

      
     

Run the following command to generate a code library:
```
dotnet build /tmp/csharp/projects/test.csproj -c Release -o /tmp/csharp/release
```
.NET directory: /home/tools/dotnetcore-sdk/dotnet-sdk-2.1.302-linux-x64/dotnet
Run the following command to go to the /tmp/csharp/release directory:
```
cd /tmp/csharp/release 
```

View the compiled .dll files in the /tmp/csharp/release directory.

-rw-r--r-- 1 root root 468480 Jan 21 16:40 Newtonsoft.Json.dll
-rw-r--r-- 1 root root   5120 Jan 21 16:40 HC.Serverless.Function.Common.JsonSerializer.dll
-rw-r--r-- 1 root root   5120 Jan 21 16:40 HC.Serverless.Function.Common.dll
-rw-r--r-- 1 root root    232 Jan 21 17:10 test.pdb
-rw-r--r-- 1 root root   3584 Jan 21 17:10 test.dll
-rw-r--r-- 1 root root   1659 Jan 21 17:10 test.deps.json

Create the test.runtimeconfig.json file in the /tmp/csharp/release directory. The file content is as follows:

{
    "runtimeOptions": {
        "framework": {
            "name": "Microsoft.NETCore.App",
            "version": "6.0.0"
        }
    }
}

Run the following command to package the test.zip file in the /tmp/csharp/release directory:
```
zip -r test.zip ./*
```

Test Example

Create a C# (.NET 6.0) event function from scratch on the FunctionGraph console and upload the test.zip file, as shown in Figure 1.
Figure 1 Uploading the code package
Configure a test event, as shown in Figure 2. The key must be set to KetTest, and the value can be customized. (The test string must be in JSON format.)
Figure 2 Configuring a test event

The attribute of the serialization class must be defined as KetTest.
Click Test and view the execution result.