如何为Powershell脚本创建可在不同计算机上运行的工作dll程序集？

Question

我有必须将 MySQL.Data.dll 加载为 MySQL\Connector 和 System.Runtime.CompilerServices.Unsafe.dll 的代码，以便我可以使用 SQL 事务

[System.Reflection.Assembly]::LoadFrom("D:\MySQL.Data.dll")
[System.Reflection.Assembly]::LoadFrom("D:\System.Runtime.CompilerServices.Unsafe.dll")

$server = "192.168.0.80"
$database = "mydb"
$user = "sql"
$password = "mypass1"

$connection = New-Object MySql.Data.MySqlClient.MySqlConnection
$connection.ConnectionString = "server=$server;database=$database;uid=$user;pwd=$password"

$connection.Open()

$transaction = $connection.BeginTransaction()

try {

    $cmd = New-Object MySql.Data.MySqlClient.MySqlCommand
    $cmd.Connection = $connection
    $cmd.Transaction = $transaction


    $cmd.CommandText = "INSERT INTO mytable (column1, column2) VALUES (@value1, @value2)"
    $cmd.Parameters.AddWithValue("@value1", "somevalue1") | Out-Null
    $cmd.Parameters.AddWithValue("@value2", "somevalue2") | Out-Null
    $cmd.ExecuteNonQuery() | Out-Null


    $transaction.Commit()

}
catch {

    if ($transaction -ne $null) {
        $transaction.Rollback()
    }
    Write-Host "Error: $_"
}
finally {

    $connection.Close()
}

问题是，我在加载这个“unsafe.dll”时遇到错误

Exception when calling "BeginTransaction" with "0" arguments: "Could not load file or assembly "System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" or one of its dependencies. The specified file could not be found."

表示 MySQL.Data.dll 试图加载此“unsafe.dll”的某个版本，但无法执行此操作。它会引发错误。 我有什么办法可以修复它吗？因为我的 Powershell 脚本中需要事务，并且由于某些问题我无法使用 SimplySQL 模块。

Answer 1

好的，可以了。问题是，您需要准确加载 4.0.4.1 版本的 System.Runtime.CompilerServices.Unsafe.dll，因为通过链接到此特定版本，仅组装（编译）并兼容任何当前的 MySQL.Data.dll。

我刚刚从 NuGet 存储库手动下载了 System.Runtime.CompilerServices.Unsafe.dll 版本 4.0.4.1。我的意思是我没有将它作为包安装，只是通过 NuGet Package Explorer 查看它并双击必要的 *.dll 进行下载。

我的代码从 Powershell 5.0 脚本到 MySQL 服务器的工作事务现在看起来像：

# | Load MySQL Connector from Windows GAC (Global Assembly Cache)
[System.Reflection.Assembly]::LoadWithPartialName("MySql.Data")

# | Set path to dll file 
$unsafe_dll_path = "D:\Connectors\from-nuget\net461\System.Runtime.CompilerServices.Unsafe.dll"

# | Load dll for trancactions
[System.Reflection.Assembly]::UnsafeLoadFrom($unsafe_dll_path)

# | define connection
$connection = New-Object MySql.Data.MySqlClient.MySqlConnection

# | Create and open connection to MySQL database
$connection = New-Object MySql.Data.MySqlClient.MySqlConnection
$connection.ConnectionString = "server=192.168.0.80;database=mydatabase;user id=sqldbwriter;password=mypassword"
$connection.Open()

# | Begin transaction
$transaction = $connection.BeginTransaction()

try {
    # | Create command
    $command = New-Object MySql.Data.MySqlClient.MySqlCommand
    $command.Connection = $connection
    $command.Transaction = $transaction

    # | Execute command in transaction's pipe
    $command.CommandText = "INSERT INTO mytable (column1, column2) VALUES ('value25', 'value26')"
    $command.ExecuteNonQuery()

    # | Commit transaction
    $transaction.Commit()
    Write-Host "Transaction success."
}
catch {
    # | Rollback  transaction incase of errors
    $transaction.Rollback()
    Write-Host "Transaction cancelled."
    throw
}
finally {
    # | Close connection
    $connection.Close()
}

此外，正如您所看到的，似乎甚至不需要从他们的网站下载 Oracle 的 MySQL\Connector，因为它已经存储在 Windows GAC（全局程序集缓存）中

GAC    Version        Location                                                                                                                                                                                                                                   
---    -------        --------                                                                                                                                                                                                                                   
True   v4.0.30319     C:\Windows\Microsoft.Net\assembly\GAC_MSIL\MySql.Data\v4.0_8.3.0.0__c5687fc88969c44d\MySql.Data.dll                                                                                                                                        
False  v4.0.30319     D:\Connectors\from-nuget\net461\System.Runtime.CompilerServices.Unsafe.dll                                                                                                                                                                 
1
Transaction success.

附注也许现在也可以使用“LoadFrom”方法而不是“UnsafeLoadFrom”。我还没查过。