用LINQ2XML计算最大和最小日期

Question

也许是一个小问题，但我不明白这里出现了什么问题。

下面的代码是针对一个XML文件（下面的示例），并通过元素'eventBlocks'的所有后代中的所有相同事件来计算绝对最小日期和绝对最大日期。 （所有'EventC'元素的最早/最近日期，...）

正如你可以看到'ElementC'（对于eaxample）的enddate之一有endDate'1/14/2011'。这应该是我的MaxDateTo值。但是结果显示“2011/1/2011”的计算maxEndDate并忽略了正确的值。

我认为比较器将其作为字符串或整数并提供错误的结果。

我需要做什么以及如何计算正确的最大和最小日期？

在此先感谢 马库斯

var xmlDoc = XDocument.Load(@"c:\Temp\MergedCalendar2011.xml"); 

    var result = from vb in xmlDoc.Descendants("eventBlock") 
       group vb by vb.Attribute("eventName").Value into blocks 
       orderby blocks.Key ascending 
       select new 
       { 
        BlockName = blocks.Key, 
        MinDateFrom = blocks.Min(min => min.Attribute("start").Value), 
        MaxDateTo = blocks.Max(max => max.Attribute("end").Value), 
       }; 

这是XML：

<?xml version="1.0" standalone="yes"?> 
<year year="2011" id="year2011"> 
    <state name="Baden Wuerttemberg" > 
    <eventBlocks> 
     <eventBlock eventName="EventX" start="4/21/2011" end="4/22/2011" /> 
     <eventBlock eventName="EventX" start="4/26/2011" end="5/1/2011" /> 
     <eventBlock eventName="EventZ" start="6/14/2011" end="6/26/2011" /> 
     <eventBlock eventName="EventA" start="7/28/2011" end="9/11/2011" /> 
     <eventBlock eventName="EventB" start="10/31/2011" end="11/1/2011" /> 
     <eventBlock eventName="EventB" start="11/2/2011" end="11/5/2011" /> 
     <eventBlock eventName="EventC" start="1/1/2011" end="1/14/2011" /> 
     <eventBlock eventName="EventC" start="12/23/2011" end="1/14/2012" /> 
    </eventBlocks> 
    </state> 
    <state name="Brandenburg" > 
    <eventBlocks> 
     <eventBlock eventName="EventY" start="1/31/2011" end="2/6/2011" /> 
     <eventBlock eventName="EventX" start="4/20/2011" end="5/1/2011" /> 
     <eventBlock eventName="EventZ" start="6/3/2011" end="6/4/2011" /> 
     <eventBlock eventName="EventA" start="6/30/2011" end="8/14/2011" /> 
     <eventBlock eventName="EventB" start="10/4/2011" end="10/15/2011" /> 
     <eventBlock eventName="EventC" start="1/1/2011" end="1/2/2011" /> 
     <eventBlock eventName="EventC" start="12/23/2011" end="1/1/2012" /> 
    </eventBlocks> 
    </state> 
    <state name="Bremen"> 
    <eventBlocks> 
     <eventBlock eventName="EventY" start="1/31/2011" end="2/2/2011" /> 
     <eventBlock eventName="EventX" start="4/16/2011" end="5/1/2011" /> 
     <eventBlock eventName="EventZ" start="6/3/2011" end="6/4/2011" /> 
     <eventBlock eventName="EventZ" start="6/14/2011" end="6/15/2011" /> 
     <eventBlock eventName="EventA" start="7/7/2011" end="8/18/2011" /> 
     <eventBlock eventName="EventB" start="10/17/2011" end="10/30/2011" /> 
     <eventBlock eventName="EventC" start="1/1/2011" end="1/6/2011" /> 
     <eventBlock eventName="EventC" start="12/23/2011" end="1/1/2012" /> 
    </eventBlocks> 
    </state> 
    </year> 

Answer 1

您应该在开始/结束的字符串转换为日期查询：

MinDateFrom = blocks.Min(min => DateTime.ParseExact(min.Attribute("start").Value, "M/d/yyyy", CultureInfo.InvariantCulture)), 
MaxDateTo = blocks.Max(max => DateTime.ParseExact(max.Attribute("end").Value, "M/d/yyyy", CultureInfo.InvariantCulture)),