c# - 无法从多个单元测试访问数据库

问题描述

我有连接字符串和一堆我的单元测试使用它来测试一些应用了一些 CRUD 操作的类的逻辑。所以我将它作为测试类中的私有常量字段传递并共享给我的测试。一切都很好！

但后来我意识到我必须把它作为集成测试来做。所以我决定使用静态助手类通过会话创建数据库，以便我测试使用它然后删除。

课程如下：

public static class LocalDB
{
    public const string DB_DIRECTORY = "Data";

    public static string GetLocalDB(string dbName, bool deleteIfExists = false)
    {
        try
        {
            var outputFolder = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), DB_DIRECTORY);
            var mdfFilename = dbName + ".mdf";
            var dbFileName = Path.Combine(outputFolder, mdfFilename);
            var logFileName = Path.Combine(outputFolder, $"{dbName}_log.ldf");

            if (!Directory.Exists(outputFolder))
            {
                Directory.CreateDirectory(outputFolder);
            }

            if (File.Exists(dbFileName) && deleteIfExists)
            {
                if (File.Exists(logFileName)) File.Delete(logFileName);
                File.Delete(dbFileName);
                CreateDatabase(dbName, dbFileName);
            }

            else if (!File.Exists(dbFileName))
            {
                CreateDatabase(dbName, dbFileName);
            }

            var connectionString = string.Format(@"Data Source=(LocalDB)\v11.0;AttachDBFileName={1};Initial Catalog={0};Integrated Security=True;", dbName, dbFileName);

            CreateTable(connectionString, "Cpa", dbName);

            return connectionString;
        }
        catch(Exception ex)
        {
            throw;
        }
    }

    public static bool CreateDatabase(string dbName, string dbFileName)
    {
        try
        {
            var connectionString = @"Data Source=(LocalDB)\v11.0;Initial Catalog=master;Integrated Security=True";

            using (var connection = new SqlConnection(connectionString))
            {
                connection.Open();

                var cmd = connection.CreateCommand();

                DetachDatabase(dbName);

                cmd.CommandText = string.Format("CREATE DATABASE {0} ON (NAME = N'{0}', FILENAME = '{1}')", dbName, dbFileName);
                cmd.ExecuteNonQuery();

                cmd.Dispose();
            }

            return File.Exists(dbFileName);
        }
        catch
        {
            throw;
        }
    }

    public static bool DetachDatabase(string dbName)
    {
        try
        {
            var connectionString = $@"Data Source=(LocalDB)\v11.0;Initial Catalog=master;Integrated Security=True";

            using (var connection = new SqlConnection(connectionString))
            {
                connection.Open();

                var cmd = connection.CreateCommand();
                cmd.CommandText = $"exec sp_detach_db '{dbName}'";
                cmd.ExecuteNonQuery();

                cmd.Dispose();
                return true;
            }
        }
        catch(Exception ex)
        {
            return false;
        }

    }

    public static bool CreateTable(string connectionString, string tableName, string dbName)
    {
        connectionString = connectionString.Replace("master", dbName);
        try
        {
            using (var connection = new SqlConnection(connectionString))
            {
                var createTableQuery = $@"CREATE TABLE {tableName}(
                                            CrmId nvarchar(50) NOT NULL,
                                            Service nvarchar(25) NOT NULL,
                                            RecurringReference nvarchar(50),
                                            ExpiryDate datetime,
                                            CardNumber nvarchar(50),
                                            Enabled bit,
                                            Brand nvarchar(50),
                                            CpaType nvarchar(50),
                                            Channel nvarchar(50)
                                                                );";

                var command = new SqlCommand(createTableQuery, connection);

                connection.Open();

                var reader = command.ExecuteReader();
                reader.Dispose();

                return true;
            }
        }
        catch (Exception ex)
        {
            return false;
        }
    }
}

我在我的测试类的 ctor amd 初始化字段中调用它的GetLocalDB方法。之后我收到以下错误“进程无法访问文件 blah log.ldf因为它被另一个进程使用”

！！！所有测试都使用相同的连接字符串，我不知道出了什么问题。对于我所做的所有更改，不可能是单元测试失败是连接字符串（用于已经存在的数据库-> 更改为临时本地（LocalDb 类））

谢谢！

标签： c#sql.netsql-serverdatabase

c# - 无法从多个单元测试访问数据库

问题描述

解决方案

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