我有一个哈希表,用于存储程序集路径的版本号。我想找到最大值的键,我已经在下面的函数中解决了这个问题。我还想找出最大值的计数是否大于 1 并将其存储在变量中。关于如何完成最后一部分的任何想法?
Function Get-LatestDacFxPath
{
[cmdletbinding()]
$knownPaths = (
'C:Program Files (x86)Microsoft Visual Studio 14.0Common7IDEExtensionsMicrosoftSQLDBDAC120',
'C:Program Files (x86)Microsoft Visual Studio 14.0Common7IDEExtensionsMicrosoftSQLDBDAC130',
'C:Program Files (x86)Microsoft Visual Studio 14.0Common7IDEExtensionsMicrosoftSQLDBDAC140',
'C:Program Files (x86)Microsoft SQL Server120DACbin',
'C:Program Files (x86)Microsoft SQL Server130DACbin',
'C:Program Files (x86)Microsoft SQL Server140DACbin',
'C:Program Files (x86)NuGetPackagesMicrosoft.Data.Tools.Msbuildlibnet40'
)
$dacAssembly = 'Microsoft.SqlServer.Dac.dll'
[hashtable]$dacVersions = @{}
foreach($dacPacPath in $knownPaths)
{
if(Test-Path($dacPacPath)) {
$dacVersions[$dacPacPath] = (Get-ItemProperty -Path (Join-Path $dacPacPath $dacAssembly)).VersionInfo.ProductVersion
}
}
$PathOfLatestVersion = ($dacVersions.GetEnumerator() | sort value -Descending | select -First 1 ).Key
$LatestVersion = ($dacVersions.GetEnumerator() | sort value -Descending | select -First 1 ).Value
}
如果您想弄清楚多个实例是否共享最大值,我会使用 Group-Object
:
$HighestValueBracket = $dacVersions.GetEnumerator() |Group Value |Sort {$_.Name -as [version]} -Descending |Select -First 1
if($HighestValueBracket.Count -gt 1){
Write-Host "Multiple instances with version $($HighestValueBracket.Name)"
}
回答这个问题的一种更简单但可能不太直观的方法是对值进行排序,并测试两个最大值是否相等:
$sortedVersionEntries = $dacVersions.GetEnumerator() |Sort Value -Descending
if($sortedVersionEntries[0].Value -eq $sortedVersionEntries[1]){
Write-Host "Multiple instances with version $($sortedVersionEntries[0].Value)"
}
我最初将问题误读为"如何在值字段中找到具有最多项目的哈希表条目?">- 如果您只想查找具有最多项目的条目,请按值字段中的对象计数进行排序:
$HashTable = @{
a = 1,2
b = 1
c = 1,2,3,4
d = 1,2,3
}
$MaxEntry = $HashTable.GetEnumerator() |Sort {@($_.Value).Count} -Descending |Select -First 1
Write-Host "Key with most entries: $($MaxEntry.Key)"
将"C"写入主机