使用 C# 连接器建立连接

创建项目

dotnet new console -o example

Add C# TDengine Driver class lib

cd example
vim example.csproj

增加下面的 ItemGroup 和 Task 配置到您的工程文件中。

<ItemGroup>
    <PackageReference Include="TDengine.Connector" Version="3.0.*" GeneratePathProperty="true" />
  </ItemGroup>
  <Target Name="copyDLLDependency" BeforeTargets="BeforeBuild">
    <ItemGroup>
      <DepDLLFiles Include="$(PkgTDengine_Connector)\runtimes\**\*.*" />
    </ItemGroup>
    <Copy SourceFiles="@(DepDLLFiles)" DestinationFolder="$(OutDir)" />
  </Target>

dotnet add package TDengine.Connector

Config

在您的终端里面执行下面的命令设置 TDengine Cloud 令牌为环境变量：

Bash
CMD
Powershell

export TDENGINE_CLOUD_DSN="<DSN>"

set TDENGINE_CLOUD_DSN=<DSN>

$env:TDENGINE_CLOUD_DSN='<DSN>'

IMPORTANT

替换 <DSN> 为真实的值，格式应该是 https(<cloud_endpoint>)/?token=<token>。

获取真实的 DSN 的值，请登录TDengine Cloud 后点击左边的”编程“菜单，然后选择”C#“。

建立连接

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="TDengine.Connector" Version="3.0.*" GeneratePathProperty="true" />
  </ItemGroup>
  <Target Name="copyDLLDependency" BeforeTargets="BeforeBuild">
    <ItemGroup>
      <DepDLLFiles Include="$(PkgTDengine_Connector)\runtimes\**\*.*" />
    </ItemGroup>
    <Copy SourceFiles="@(DepDLLFiles)" DestinationFolder="$(OutDir)" />
  </Target>

</Project>

查看源码

using System;
using TDengineWS.Impl;

namespace Cloud.Examples
{
    public class ConnectExample
    {
        static void Main(string[] args)
        {
            string dsn = Environment.GetEnvironmentVariable("TDENGINE_CLOUD_DSN");
            Connect(dsn);
        }

        public static void Connect(string dsn)
        {
            // get connect
            IntPtr conn = LibTaosWS.WSConnectWithDSN(dsn);
            if (conn == IntPtr.Zero)
            {
                throw new Exception($"get connection failed,reason:{LibTaosWS.WSErrorStr(conn)},code:{LibTaosWS.WSErrorNo(conn)}");
            }
            else
            {
                Console.WriteLine("Establish connect success.");
            }

            // do something ...

            // close connect
            LibTaosWS.WSClose(conn);

        }
    }
}