PowerShell - 替换 csv 文件中特定列中的字符

Question

我需要在许多 csv 文件中将 "-" 替换为 ""(什么也没有)，除了 Name 列，该列可能包含我需要保留的 - 字符。

例如:

"Name","timestamp","CPU|Demand (%)","CPU|Demand (%) (Trend)","CPU|Demand (%) (30 days forecast)"
"ZY02-LAB-WinMachine","Mar 2, 2017 12:01:19 AM","-","38.07","-"
"ZY02-LAB-WinMachine","Mar 21, 2017 10:45:00 AM","40.55","-","-"
"ZY02-LAB-WinMachine","Apr 6, 2017 11:56:19 AM","-","-","38.69"
"ZY02-LAB-WinMachine","Apr 6, 2017 12:11:19 PM","-","-","38.7"

will become

"Name","timestamp","CPU|Demand (%)","CPU|Demand (%) (Trend)","CPU|Demand (%) (30 days forecast)"
"ZY02-LAB-WinMachine","Mar 2, 2017 12:01:19 AM","","38.07",""
"ZY02-LAB-WinMachine","Mar 21, 2017 10:45:00 AM","40.55","",""
"ZY02-LAB-WinMachine","Apr 6, 2017 11:56:19 AM","","","38.69"
"ZY02-LAB-WinMachine","Apr 6, 2017 12:11:19 PM","","","38.7"

The line I have in my script replaces ALL - in the csv .. even the Name column :-(

(Get-Content $ImportCPUFile) | % {$_ -replace "-"} | out-file -FilePath CSV-cleaned.csv -Fo -En ascii

Answer 1

尝试这样的事情:

$Csv = Import-Csv -Path $ImportCPUFile;
$Headers = $Csv | Get-Member -MemberType NoteProperty | Select-Object -ExpandProperty Name;

ForEach ($Record in $Csv) {
    foreach ($Header in $Headers) {
        if ($Record.$Header -eq '-') {
            $Record.$Header = [String]::Empty;
        }
    }
}

$Csv | Export-Csv -Path $OutputFile -NoTypeInformation;

如果某些字段中有前导或尾随空格，您可能需要使用 $Record.$Header.Trim() -eq '-' 进行比较。