Question

如何使用#Requires关键字检查特定的dll？这是我的代码，它要求文件Microsoft.Search.Interop.dll与脚本位于同一文件夹中。

# Load DLL containing classes & interfaces
Add-Type -path "Microsoft.Search.Interop.dll"

# Provides methods for controlling the Search service. This 
# interface manages settings and objects that affect the search engine 
# across catalogs. 
#
# https://msdn.microsoft.com/en-us/library/bb231485(v=vs.85).aspx
$sm = New-Object Microsoft.Search.Interop.CSearchManagerClass

# Retrieves a catalog by name and creates a new ISearchCatalogManager 
# object for that catalog.
$catalog = $sm.GetCatalog("SystemIndex")

# Resets the underlying catalog by rebuilding the databases 
# and performing a full indexing. 
#
# https://msdn.microsoft.com/en-us/library/bb266414(v=vs.85).aspx
$catalog.Reset()

Answer 1

如果您只想检查文件系统（即与脚本位于同一文件夹中）或GAC中是否存在特定程序集，那么测试程序集是否存在的简单函数就足够了。

该函数将接受带或不带路径的程序集名称。它测试脚本文件夹中的程序集（如果没有路径元素）。然后，如果指定了searchGAC param，则在GAC中测试是否存在。如果它在任何地方找到程序集，它将加载它，否则，将抛出异常。

# requires function
function Get-Assembly ([string]$dllName, [switch]$searchGAC) {
  if ($dllName.Split('\\').Count -eq 1) {
    $dllName = Join-Path $PSScriptRoot $dllName
  }
  if (Test-Path $dllName -PathType Leaf) {
    Add-Type -path $dllName
  } else {
    $found = $false
  }
  if (!$found -and $searchGAC) {
    $dllName = ($dllName -split '\\')[-1]
    $assembly = [appdomain]::CurrentDomain.GetAssemblies() | Select -ExpandProperty Modules | where {$_.Name -match $dllName}
    if ($assembly) {
      [void][System.Reflection.Assembly]::Load($assembly.Assembly.FullName)
      $found = $true
    }
  }
  if (!$found) {
    throw [System.IO.FileNotFoundException] "$dllName not found."
  }
}
Set-Alias -Name Requires -Value Get-Assembly -Force


# your code from here, with the requires added in
# Load DLL containing classes & interfaces
Requires -dllName 'Microsoft.Search.Interop.dll' -searchGAC

# Provides methods for controlling the Search service. This 
# interface manages settings and objects that affect the search engine 
# across catalogs. 
#
# https://msdn.microsoft.com/en-us/library/bb231485(v=vs.85).aspx
$sm = New-Object Microsoft.Search.Interop.CSearchManagerClass

# Retrieves a catalog by name and creates a new ISearchCatalogManager 
# object for that catalog.
$catalog = $sm.GetCatalog("SystemIndex")

# Resets the underlying catalog by rebuilding the databases 
# and performing a full indexing. 
#
# https://msdn.microsoft.com/en-us/library/bb266414(v=vs.85).aspx
$catalog.Reset()

如何使用DLL的#Requires关键字？

1 个答案: