如何使用Powershell读取XML和编写CSV



如何将books.xml转换为CSV并写入文件?

PS /home/nicholas/xml> 
PS /home/nicholas/xml> $books = Import-Clixml books.xml 
PS /home/nicholas/xml> 
PS /home/nicholas/xml> $books.InnerXml                  
<?xml version="1.0"?><catalog><book id="bk101"><author>Gambardella, Matthew</author><title>XML Developer's Guide</title><genre>Computer</genre><price>44.95</price><publish_date>2000-10-01</publish_date><description>An in-depth look at creating applications 
with XML.</description></book><book id="bk102"><author>Ralls, Kim</author><title>Midnight Rain</title><genre>Fantasy</genre><price>5.95</price><publish_date>2000-12-16</publish_date><description>A former architect battles corporate zombies, 
an evil sorceress, and her own childhood to become queen 
of the world.</description></book><book id="bk103"><author>Corets, Eva</author><title>Maeve Ascendant</title><genre>Fantasy</genre><price>5.95</price><publish_date>2000-11-17</publish_date><description>After the collapse of a nanotechnology 
society in England, the young survivors lay the 
foundation for a new society.</description></book><book id="bk104"><author>Corets, Eva</author><title>Oberon's Legacy</title><genre>Fantasy</genre><price>5.95</price><publish_date>2001-03-10</publish_date><description>In post-apocalypse England, the mysterious 
agent known only as Oberon helps to create a new life 
for the inhabitants of London. Sequel to Maeve 
Ascendant.</description></book><book id="bk105"><author>Corets, Eva</author><title>The Sundered Grail</title><genre>Fantasy</genre><price>5.95</price><publish_date>2001-09-10</publish_date><description>The two daughters of Maeve, half-sisters, 
battle one another for control of England. Sequel to 
Oberon's Legacy.</description></book><book id="bk106"><author>Randall, Cynthia</author><title>Lover Birds</title><genre>Romance</genre><price>4.95</price><publish_date>2000-09-02</publish_date><description>When Carla meets Paul at an ornithology 
conference, tempers fly as feathers get ruffled.</description></book><book id="bk107"><author>Thurman, Paula</author><title>Splish Splash</title><genre>Romance</genre><price>4.95</price><publish_date>2000-11-02</publish_date><description>A deep sea diver finds true love twenty 
thousand leagues beneath the sea.</description></book><book id="bk108"><author>Knorr, Stefan</author><title>Creepy Crawlies</title><genre>Horror</genre><price>4.95</price><publish_date>2000-12-06</publish_date><description>An anthology of horror stories about roaches,
centipedes, scorpions  and other insects.</description></book><book id="bk109"><author>Kress, Peter</author><title>Paradox Lost</title><genre>Science Fiction</genre><price>6.95</price><publish_date>2000-11-02</publish_date><description>After an inadvertant trip through a Heisenberg
Uncertainty Device, James Salway discovers the problems 
of being quantum.</description></book><book id="bk110"><author>O'Brien, Tim</author><title>Microsoft .NET: The Programming Bible</title><genre>Computer</genre><price>36.95</price><publish_date>2000-12-09</publish_date><description>Microsoft's .NET initiative is explored in 
detail in this deep programmer's reference.</description></book><book id="bk111"><author>O'Brien, Tim</author><title>MSXML3: A Comprehensive Guide</title><genre>Computer</genre><price>36.95</price><publish_date>2000-12-01</publish_date><description>The Microsoft MSXML3 parser is covered in 
detail, with attention to XML DOM interfaces, XSLT processing, 
SAX and more.</description></book><book id="bk112"><author>Galos, Mike</author><title>Visual Studio 7: A Comprehensive Guide</title><genre>Computer</genre><price>49.95</price><publish_date>2001-04-16</publish_date><description>Microsoft Visual Studio 7 is explored in depth,
looking at how Visual Basic, Visual C++, C#, and ASP+ are 
integrated into a comprehensive development 
environment.</description></book></catalog>
PS /home/nicholas/xml> 
PS /home/nicholas/xml> $books | Export-Csv books.csv      
PS /home/nicholas/xml> 
PS /home/nicholas/xml> cat ./books.csv
"xml","catalog"
"version=""1.0""","System.Xml.XmlElement"
PS /home/nicholas/xml> 

看起来$csv是被转换的,但它是如何被写成CSV文件的呢?

转换为JSON并没有好到哪里去:

PS /home/nicholas/xml> 
PS /home/nicholas/xml> 
PS /home/nicholas/xml> $books | ConvertTo-Json          
WARNING: Resulting JSON is truncated as serialization has exceeded the set depth of 2.
[
[],
[
[
"System.Xml.XmlElement",
"System.Xml.XmlElement",
"System.Xml.XmlElement",

即使深度为9或更大。

这是$books:的输出

PS /home/nicholas/xml> 
PS /home/nicholas/xml> $books
xml           catalog
---           -------
version="1.0" catalog
PS /home/nicholas/xml> $books.ChildNodes
Version         : 1.0
Encoding        : 
Standalone      : 
Value           : version="1.0"
InnerText       : version="1.0"
Name            : xml
LocalName       : xml
NodeType        : XmlDeclaration
PreviousSibling : 
NextSibling     : catalog
ParentNode      : #document
ChildNodes      : {}
Attributes      : 
OwnerDocument   : #document
FirstChild      : 
LastChild       : 
HasChildNodes   : False
NamespaceURI    : 
Prefix          : 
IsReadOnly      : False
OuterXml        : <?xml version="1.0"?>
InnerXml        : 
SchemaInfo      : System.Xml.Schema.XmlSchemaInfo
BaseURI         : 
PreviousText    : 
book : {book, book, book, book…}

PS/home/nicholas/xml>

与CCD_ 7相差甚远。

Import-Clixml不是用于导入任意XML文档;它仅设计用于处理包含CLIXML数据的XML文档,CLIXML数据是一种基于XML的序列化格式,用于表示的实例。NET类型用于跨进程通信,例如由Export-Clixml生成。CLIXML通常在PowerShell远程处理(以及更普遍的跨进程通信(中的幕后中使用。

也许令人惊讶的是,没有通用cmdlet用于导入任意XML文档(但是,有一个cmdlet用于查询和提取XML文档中的数据,即Select-Xml(。

您必须使用[xml]类型(System.Xml.XmlDocument(将XML数据导入DOM,然后DOM允许您将数据转换为不同的格式:

# Load and parse the XML file into a DOM.
($xmlDoc = [xml]::new()).Load((Convert-Path books.xml))
# Export the book child elements of the catalog element to a CSV file.
$xmlDoc.catalog.book | Export-Csv books.csv
# Parse the CSV file into objects ([pscustomobject] instances)
# and output them to the console with friendly formatting.
Import-Csv books.csv

注意:在Windows PowerShell中,请考虑将-NoTypeInformationExport-Csv一起使用,以及使用-Encoding参数来控制输出字符编码,默认值为ASCII(!(。幸运的是,在PowerShell(Core(7+中,-NoTypeInformation现在是隐含的,默认字符编码是(无BOM(UTF-8。

输出:

id           : bk101
author       : Gambardella, Matthew
title        : XML Developer's Guide
genre        : Computer
price        : 44.95
publish_date : 2000-10-01
description  : An in-depth look at creating applications 
with XML.
id           : bk102
author       : Ralls, Kim
title        : Midnight Rain
genre        : Fantasy
price        : 5.95
publish_date : 2000-12-16
description  : A former architect battles corporate zombies, 
an evil sorceress, and her own childhood to become queen 
of the world.
id           : bk103
author       : Corets, Eva
title        : Maeve Ascendant
genre        : Fantasy
price        : 5.95
publish_date : 2000-11-17
description  : After the collapse of a nanotechnology 
society in England, the young survivors lay the 
foundation for a new society.
id           : bk104
author       : Corets, Eva
title        : Oberon's Legacy
genre        : Fantasy
price        : 5.95
publish_date : 2001-03-10
description  : In post-apocalypse England, the mysterious 
agent known only as Oberon helps to create a new life 
for the inhabitants of London. Sequel to Maeve 
Ascendant.
id           : bk105
author       : Corets, Eva
title        : The Sundered Grail
genre        : Fantasy
price        : 5.95
publish_date : 2001-09-10
description  : The two daughters of Maeve, half-sisters, 
battle one another for control of England. Sequel to 
Oberon's Legacy.
id           : bk106
author       : Randall, Cynthia
title        : Lover Birds
genre        : Romance
price        : 4.95
publish_date : 2000-09-02
description  : When Carla meets Paul at an ornithology 
conference, tempers fly as feathers get ruffled.
id           : bk107
author       : Thurman, Paula
title        : Splish Splash
genre        : Romance
price        : 4.95
publish_date : 2000-11-02
description  : A deep sea diver finds true love twenty 
thousand leagues beneath the sea.
id           : bk108
author       : Knorr, Stefan
title        : Creepy Crawlies
genre        : Horror
price        : 4.95
publish_date : 2000-12-06
description  : An anthology of horror stories about roaches,
centipedes, scorpions  and other insects.
id           : bk109
author       : Kress, Peter
title        : Paradox Lost
genre        : Science Fiction
price        : 6.95
publish_date : 2000-11-02
description  : After an inadvertant trip through a Heisenberg
Uncertainty Device, James Salway discovers the problems 
of being quantum.
id           : bk110
author       : O'Brien, Tim
title        : Microsoft .NET: The Programming Bible
genre        : Computer
price        : 36.95
publish_date : 2000-12-09
description  : Microsoft's .NET initiative is explored in 
detail in this deep programmer's reference.
id           : bk111
author       : O'Brien, Tim
title        : MSXML3: A Comprehensive Guide
genre        : Computer
price        : 36.95
publish_date : 2000-12-01
description  : The Microsoft MSXML3 parser is covered in 
detail, with attention to XML DOM interfaces, XSLT processing, 
SAX and more.
id           : bk112
author       : Galos, Mike
title        : Visual Studio 7: A Comprehensive Guide
genre        : Computer
price        : 49.95
publish_date : 2001-04-16
description  : Microsoft Visual Studio 7 is explored in depth,
looking at how Visual Basic, Visual C++, C#, and ASP+ are 
integrated into a comprehensive development 
environment.

尝试以下操作:

using assembly System
using assembly System.Collections
using assembly System.Xml.Linq
using assembly System.IO
$inputFilename = "c:temptest.xml"
$outputFilename = "c:temptest.csv"

$doc = [System.Xml.Linq.XDocument]::Load($inputFilename)
$writer = New-Object System.IO.StreamWriter($outputFilename)
$header = "id,author,title,genre,price,publish,description"
$writer.Writeline($header)
$books = $doc.Descendants("book")
foreach($book in $books)
{

$id =  $book.Attribute("id").Value
$author = $book.Element("author").Value
$title = $book.Element("title").Value
$genre = $book.Element("genre").Value
$price = $book.Element("price").Value
$date = $book.Element("publish_date").Value
$description = $book.Element("description").Value
$lineArray = @($id,$author,$title,$genre,$price,$date,$description)
Write-Host $lineArray
$line = [String]::Join(",", $lineArray)
Write-Host $line
$writer.Writeline($line)
}
$writer.Flush()
$writer.Close()

我更新下方的代码

  1. 在字段周围添加了双引号,因为数据包含逗号。

  2. 合并描述字段以使用Regex删除回车和额外空格。

    使用装配系统使用装配系统。集合使用装配系统。Xml。林克使用装配系统。IO使用装配系统。文本RegularExpressions

    $inputFilename="c: \temp\test.xml"$outputFilename=";c: \temp\test.csv">

    $doc=[System.Xml.Linq.XDocument]::加载($inputFilename($writer=新对象系统。IO.StreamWriter($outputFilename($headerArray=@("id"、"author"、"title"、"types"、"price"、"publish"one_answers"description"($header=[String]::Join(",",$headerArray($writer。写线("+$头+"(

    $books=$doc。后裔("书"(

    foreach($books中的$books({

    $id =  $book.Attribute("id").Value
    $author = $book.Element("author").Value
    $title = $book.Element("title").Value
    $genre = $book.Element("genre").Value
    $price = $book.Element("price").Value
    $date = $book.Element("publish_date").Value
    $description = $book.Element("description").Value
    $description = [System.Text.RegularExpressions.Regex]::Replace($description, "s+", " ");
    $lineArray = @($id,$author,$title,$genre,$price,$date,$description)
    #Write-Host $lineArray
    $line = """" + [String]::Join(""",""", $lineArray) + """" 
    #Write-Host $line
    $writer.Writeline($line)
    

    }$writer。Flush(($writer。关闭((

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