这可以缩短吗(使用VB.NET将LINQ转换为XML)?
我有下面的代码,顺便说一下,它可以工作,但我正在努力使它更短,并使用XML速记。到目前为止一切都很好,但是否有办法缩短最后几项,似乎有很多元素调用:这可以缩短吗(使用VB.NET将LINQ转换为XML)?,vb.net,linq-to-xml,Vb.net,Linq To Xml,我有下面的代码,顺便说一下,它可以工作,但我正在努力使它更短,并使用XML速记。到目前为止一切都很好,但是否有办法缩短最后几项,似乎有很多元素调用: Public Function ParseRates() As IEnumerable(Of RoomRate) Try For Each n As XElement In _xDoc...<_ns:RoomRate> _rates.Add(New RoomRate With { _
Public Function ParseRates() As IEnumerable(Of RoomRate)
Try
For Each n As XElement In _xDoc...<_ns:RoomRate>
_rates.Add(New RoomRate With { _
.GuaranteeSurchargeRequired = n.@GuaranteeSurchargeRequired, _
.IATACharacteristicIdentification = n.@IATACharacteristicIdentification, _
.IATAProductIdentification = n.@IATAProductIdentification, _
.RPH = n.@RPH, _
.CancellationPolicy = n...<_ns:AdditionalInfo>.<_ns:CancelPolicy>.@Numeric, _
.Commission = n...<_ns:AdditionalInfo>.<_ns:Commission>.@NonCommission, _
.Rate = n.Element(_ns + "Rates").Element(_ns + "Rate").Attribute("Amount").Value, _
.CurrencyCode = n.Element(_ns + "Rates").Element(_ns + "Rate").Attribute("CurrencyCode").Value,
.TotalPrice = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Attribute("Amount").Value, _
.Disclaimer = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Element(_ns + "Disclaimer").Value, _
.Surcharge = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Element(_ns + "TotalSurcharges").Attribute("Amount").Value})
Next
Return _rates
Catch ex As Exception
ErrorMessage = ex.Message
Return Nothing
End Try
End Function
公共函数ParseRates()作为IEnumerable(指RoomRate)
尝试
对于_xDoc中的每个n作为元素。。。
_使用{_
.GuaranteSourceRequired=n.@GuaranteSourceRequired_
.IATACharacteristicIdentification=n.@IATACharacteristicIdentification_
.IATAProductIdentification=n.@IATAProductIdentification_
.RPH=n.@RPH_
.CancellationPolicy=n..@数值_
.Commission=n.…@非委任_
.Rate=n.Element(_ns+“Rates”).Element(_ns+“Rate”).Attribute(“Amount”).Value_
.CurrencyCode=n.Element(_ns+“Rates”).Element(_ns+“Rate”).Attribute(“CurrencyCode”).Value,
.TotalPrice=n.Element(_ns+“Rates”).Element(_ns+“Rate”).Element(_ns+“HotelTotalPricing”).Attribute(“Amount”).Value_
.Disclaimer=n.Element(_ns+“Rates”).Element(_ns+“Rate”).Element(_ns+“HotelTotalPricing”).Element(_ns+“Disclaimer”).Value_
.附加费=n.Element(_ns+“费率”).Element(_ns+“费率”).Element(_ns+“HotelTotalPricing”).Element(_ns+“总附加费”).Attribute(“金额”).Value})
下一个
回报率
特例
ErrorMessage=ex.Message
一无所获
结束尝试
端函数
下面是用上述代码解析的XML片段
<HotelPropertyDescriptionRS xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" TimeStamp="2013-12-30T18:49:36" Version="1.14.1">
<Success xmlns="http://webservices.sabre.com/sabreXML/2003/07" />
<RoomStay xmlns="http://webservices.sabre.com/sabreXML/2003/07">
<RoomRates>
<RoomRate GuaranteeSurchargeRequired="G" IATACharacteristicIdentification="BGGO00" IATAProductIdentification="BLOOMBERG" RPH="001">
<AdditionalInfo>
<CancelPolicy Numeric="06" />
<Commission NonCommission="true">NON COMMISSIONABLE</Commission>
<Text>BLOOMBERG LP, 0.0 KM, INCLUDES BREAKFAST, INTERNET, WIFI, SEE</Text>
<Text>RATE RULES DELUXE ROOM, GUEST ROOM, 1 KING OR 2 TWIN/SINGLE BE</Text>
</AdditionalInfo>
<Rates>
<Rate Amount="66.600" CurrencyCode="KWD">
<AdditionalGuestAmounts>
<AdditionalGuestAmount MaxExtraPersonsAllowed="0">
<Charges ExtraPerson="0" />
</AdditionalGuestAmount>
</AdditionalGuestAmounts>
<HotelTotalPricing Amount="76.590">
<Disclaimer>INCLUDES TAXES AND SURCHARGES</Disclaimer>
<TotalSurcharges Amount="9.990" />
</HotelTotalPricing>
</Rate>
</Rates>
</RoomRate>
</RoomRates>
</HotelPropertyDescriptionRS>
不可佣金
BLOOMBERG LP,0.0公里,包括早餐、互联网、WIFI,请参见
价格规则豪华房、客房、1张大床或2张双人床/单人床
包括税费和附加费
谈到这一部分:
.Rate = n.Element(_ns + "Rates").Element(_ns + "Rate").Attribute("Amount").Value, _
.CurrencyCode = n.Element(_ns + "Rates").Element(_ns + "Rate").Attribute("CurrencyCode").Value,
.TotalPrice = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Attribute("Amount").Value, _
.Disclaimer = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Element(_ns + "Disclaimer").Value, _
.Surcharge = n.Element(_ns + "Rates").Element(_ns + "Rate").Element(_ns + "HotelTotalPricing").Element(_ns + "TotalSurcharges").Attribute("Amount").Value})
还有其他一些方法可以获得这5个值。首先,使用.subjections()
并获取返回的第一个元素:
.Rate = n.Descendants(_ns + "Rate").First().Attribute("Amount").Value, _
.CurrencyCode = n.Descendants(_ns + "Rate").First().Attribute("CurrencyCode").Value,
.TotalPrice = n.Descendants(_ns + "HotelTotalPricing").First().Attribute("Amount").Value, _
.Disclaimer = n.Descendants(_ns + "Disclaimer").First().Value, _
.Surcharge = n.Descendants(_ns + "TotalSurcharges").First().Attribute("Amount").Value})
元素()
仅搜索当前元素的直接子元素时,子元素()
可以为您带来当前元素的任何子元素。另一个选项是使用XPath:
.Rate = n.XPathSelectElement(".//n:Rate", nsm).Attribute("Amount").Value, _
.CurrencyCode = n.XPathSelectElement(".//n:Rate", nsm).Attribute("CurrencyCode").Value,
.TotalPrice = n.XPathSelectElement(".//n:HotelTotalPricing", nsm).Attribute("Amount").Value, _
.Disclaimer = n.XPathSelectElement(".//n:Disclaimer", nsm).Value, _
.Surcharge = n.XPathSelectElement(".//n:TotalSurcharges", nsm).Attribute("Amount").Value
在这种情况下,您需要首先定义要在XPath表达式中使用的前缀:
Dim nsm As XmlNamespaceManager = New XmlNamespaceManager(New NameTable)
nsm.AddNamespace("n", "http://webservices.sabre.com/sabreXML/2003/07")
并添加导入:
Imports System.Xml.XPath
从方法样式切换到XPath很简单。这是有关XPath语法的基础知识:
表达式前面的点(
)指示从当前节点搜索。如果没有它,表达式将从根节点求值
双斜杠(/
)类似于子体()
单斜杠(/
)类似于Element()
或Elements()
如何使用AddRange
并在其中使用LINQ查询
您可以使用Let
稍微简化查询:
Dim query = From n In _xDoc...<_ns:RoomRate>
Let additionalInfo = n...<_ns:AdditionalInfo>
Let rate = n.<_ns:Rates>.<_ns:Rate>
Let hotelPricing = rate.<_ns:HotelTotalPricing>
Select New RoomRate With {
.GuaranteeSurchargeRequired = n.@GuaranteeSurchargeRequired, _
.IATACharacteristicIdentification = n.@IATACharacteristicIdentification, _
.IATAProductIdentification = n.@IATAProductIdentification, _
.RPH = n.@RPH, _
.CancellationPolicy = additionalInfo.<_ns:CancelPolicy>.@Numeric, _
.Commission = additionalInfo.<_ns:Commission>.@NonCommission, _
.Rate = rate.@Amount, _
.CurrencyCode = rate.@CurrencyCode,
.TotalPrice = hotelPricing.@Amount, _
.Disclaimer = hotelPricing.<_ns:Disclaimer>.Value, _
.Surcharge = hotelPricing.<_ns:TotalSurcharges>.@Amount
}
为什么不先存储rates和rate元素呢?非常感谢!我从来不知道Let函数(我相信它就是这样)的存在。记录在案,有没有关于LINQ到XML的好教程的站点?Let
是一个关键字,通常是LINQ的一部分,因此您可能应该从LINQ教程开始,而不是从LINQ到XML的特定站点开始。
Imports <xmlns:_ns="test">
_rates.AddRange(query)