Azure Functions v2来自应用程序设置的Connectionstring

Question

我创建了一个简单的Azure Functions v2 Web服务，它连接到Azure SQL数据库，运行带有3个参数的存储过程，并将结果作为JSON输出返回。它现在可以正常工作（使用run.csx文件中的connectionstring）。

但是如何从应用程序设置中获取连接字符串呢？

我在这里和其他地方尝试了各种指南。但我能找到的是一长串参考文献和一堆我需要添加的代码。我已经按照指南（也在应用程序设置中设置了值），但它不会工作。我对C＃很新，所以我可能只是不明白我应该做什么。

无论如何，这是我的代码和建议的修复，据我所知：

#r "Newtonsoft.Json"
#r "System.Data"
using System.Net;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;
using System.Data;
using System.Data.SqlClient;

public static async Task<ActionResult> Run(HttpRequest req, ILogger log)
{
   log.LogInformation("C# HTTP trigger function processed a request.");

   string login = req.Query["login"];
   string pwd = req.Query["password"];
   string TransID = req.Query["TransID"];

   string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
   dynamic data = JsonConvert.DeserializeObject(requestBody);
   login = login ?? data?.login;
   pwd = pwd ?? data?.password;
   TransID = TransID ?? data?.TransID;

   var cnnString = "Server=MyServer;Database=WebServices;User Id=MyUser;Password=MyPassword;Encrypt=True;";

        try
        {
            DataTable table = new DataTable();
            SqlConnection connection = new SqlConnection(cnnString);
            SqlCommand cmd = new SqlCommand("sp_GetRegRW", connection);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.Add(new SqlParameter("@Login", login));
            cmd.Parameters.Add(new SqlParameter("@Password", pwd));
            cmd.Parameters.Add(new SqlParameter("@TransID", TransID));
            await connection.OpenAsync();
            using (SqlDataAdapter adapter = new SqlDataAdapter(cmd))
            {
                adapter.Fill(table);
            }

            return (ActionResult)new OkObjectResult(JsonConvert.SerializeObject(table));
        }
        catch (SqlException sqlex)
        {
            return (ActionResult)new OkObjectResult($"The following SqlException happened: {sqlex.Message}");
        }
        catch (Exception ex)
        {
            return (ActionResult)new OkObjectResult($"The following Exception happened: {ex.Message}");
        }

}

建议解决方案

#r "Newtonsoft.Json"
#r "System.Data"
#r "Microsoft.Extensions.Configuration"
using System.Net;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;
using System.Data;
using System.Data.SqlClient;
using Microsoft.Extensions.Configuration;

public static async Task<ActionResult> Run(HttpRequest req, ILogger log, ExecutionContext context)
{
   var config = new ConfigurationBuilder()
    .SetBasePath(context.FunctionAppDirectory)
    .AddJsonFile("local.settings.json", optional: true, reloadOnChange: true)
    .AddEnvironmentVariables()
    .Build();

   var cnnString =config.GetConnectionString("connWS");
   var setting1 = config["Setting1"];

   log.LogInformation(cnnString);
   log.LogInformation(setting1);
   log.LogInformation("C# HTTP trigger function processed a request.");

   string login = req.Query["login"];
   string pwd = req.Query["password"];
   string TransID = req.Query["TransID"];

   string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
   dynamic data = JsonConvert.DeserializeObject(requestBody);
   login = login ?? data?.login;
   pwd = pwd ?? data?.password;
   TransID = TransID ?? data?.TransID;

        try
        {
            DataTable table = new DataTable();
            SqlConnection connection = new SqlConnection(cnnString);
            SqlCommand cmd = new SqlCommand("sp_GetRegRW", connection);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.Add(new SqlParameter("@Login", login));
            cmd.Parameters.Add(new SqlParameter("@Password", pwd));
            cmd.Parameters.Add(new SqlParameter("@TransID", TransID));
            await connection.OpenAsync();
            using (SqlDataAdapter adapter = new SqlDataAdapter(cmd))
            {
                adapter.Fill(table);
            }

            return (ActionResult)new OkObjectResult(JsonConvert.SerializeObject(table));
        }
        catch (SqlException sqlex)
        {
            return (ActionResult)new OkObjectResult($"The following SqlException happened: {sqlex.Message}");
        }
        catch (Exception ex)
        {
            return (ActionResult)new OkObjectResult($"The following Exception happened: {ex.Message}");
        }

}

Answer 1

在函数v2中，您应该使用Environment.GetEnvironmentVariable("string_name",EnvironmentVariableTarget.Process)从应用程序设置和连接字符串中获取值。

注意：使用上述方法时，第一个参数取决于Type。这意味着当连接字符串的类型为SQLAZURE时，则第一个参数应为SQLAZURE + CONNSTR + _stringName。

屏幕截图如下：

代码示例：

//for connection string
string connStr = Environment.GetEnvironmentVariable("SQLAZURECONNSTR_sqldb_connection",EnvironmentVariableTarget.Process);
log.LogInformation("the connection string is: " + connStr);

结果快照：

我收到以下错误：ConnectionString属性尚未初始化。

您应该创建一个SqlConnection实例，使用您的连接字符串并在尝试发出任何命令之前打开此连接。

SqlConnection con = new SqlConnection("connStr");
await con.OpenAsync();