這裏是將檢查的CSV文件中的空函數(返回True
如果是空的,False
否則):
- 可以跳過標題
- 工程在PS 2.0(PS 2.0有不
-ReadCount
開關Get-Content
小命令)
- 不在存儲器加載整個文件
- 意識到CSV文件結構的(不會計數空/無效的行)。
它接受下列參數:
- 文件名:路徑CSV文件。
- MaxLine:從文件中讀取的最大行數。
- NOHEADER:如果沒有指定此開關,功能將跳過該文件的第一行
用例:
Test-IsCsvEmpty -FileName 'c:\foo.csv' -MaxLines 2 -NoHeader
function Test-IsCsvEmpty
{
Param
(
[Parameter(Mandatory = $true, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true)]
[string]$FileName,
[Parameter(ValueFromPipelineByPropertyName = $true)]
[ValidateRange(1, [int]::MaxValue)]
[int]$MaxLines = 2,
[Parameter(ValueFromPipelineByPropertyName = $true)]
[switch]$NoHeader
)
Begin
{
# Setup regex for CSV parsing
$DQuotes = '"'
$Separator = ','
# http://stackoverflow.com/questions/15927291/how-to-split-a-string-by-comma-ignoring-comma-in-double-quotes
$SplitRegex = "$Separator(?=(?:[^$DQuotes]|$DQuotes[^$DQuotes]*$DQuotes)*$)"
}
Process
{
# Open file in StreamReader
$InFile = New-Object -TypeName System.IO.StreamReader -ArgumentList $FileName -ErrorAction Stop
# Set inital values for Raw\Data lines count
$CsvRawLinesCount = 0
$CsvDataLinesCount = 0
# Loop over lines in file
while(($line = $InFile.ReadLine()) -ne $null)
{
# Increase Raw line counter
$CsvRawLinesCount++
# Skip header, if requested
if(!$NoHeader -and ($CsvRawLinesCount -eq 1))
{
continue
}
# Stop processing if MaxLines limit is reached
if($CsvRawLinesCount -gt $MaxLines)
{
break
}
# Try to parse line as CSV
if($line -match $SplitRegex)
{
# If success, increase CSV Data line counter
$CsvDataLinesCount++
}
}
}
End
{
# Close file, dispose StreamReader
$InFile.Close()
$InFile.Dispose()
# Write result to the pipeline
if($CsvDataLinesCount -gt 0)
{
$false
}
else
{
$true
}
}
}