C# 如何将查询语法转换为方法语法

我在胡闹，想了解林克的来龙去脉。我想将下面的查询（工作正常）从查询语法转换为方法语法，但似乎无法正确执行。有人能告诉我实现这一目标的正确方法吗

var logQuery = from entry in xDoc.Descendants("logentry")
               where (entry.Element("author").Value.ToLower().Contains(matchText) ||
                      entry.Element("msg").Value.ToLower().Contains(matchText) ||
                      entry.Element("paths").Value.ToLower().Contains(matchText) ||
                      entry.Element("revision").Value.ToLower().Contains(matchText))
               select new
               {
                   Revision = entry.Attribute("revision").Value,
                   Author = entry.Element("author").Value,
                   CR = LogFormatter.FormatCR(entry.Element("msg").Value),
                   Date = LogFormatter.FormatDate(entry.Element("date").Value),
                   Message = LogFormatter.FormatComment(entry.Element("msg").Value),
                   ET = LogFormatter.FormatET(entry.Element("msg").Value),
                   MergeFrom = LogFormatter.FormatMergeFrom(entry.Element("msg").Value),
                   MergeTo = LogFormatter.FormatMergeTo(entry.Element("msg").Value)
               };

---

其实很简单,

from entry in A
where B

翻译（字面意思）为：

以及：

直接翻译为（以“条目”作为上下文）：

（除了当它是

entry=>entry

时，编译器在非平凡的情况下会忽略它）

所以只要注射这些，你就完成了：

var logQuery = xDoc.Descendants("logentry")
               .Where(entry=>
                          entry.Element("author").Value.ToLower().Contains(matchText) ||
                          entry.Element("msg").Value.ToLower().Contains(matchText) ||
                          entry.Element("paths").Value.ToLower().Contains(matchText) ||
                          entry.Element("revision").Value.ToLower().Contains(matchText))
                .Select(entry=>new
                   {
                       Revision = entry.Attribute("revision").Value,
                       Author = entry.Element("author").Value,
                       CR = LogFormatter.FormatCR(entry.Element("msg").Value),
                       Date = LogFormatter.FormatDate(entry.Element("date").Value),
                       Message = LogFormatter.FormatComment(entry.Element("msg").Value),
                       ET = LogFormatter.FormatET(entry.Element("msg").Value),
                       MergeFrom = LogFormatter.FormatMergeFrom(entry.Element("msg").Value),
                       MergeTo = LogFormatter.FormatMergeTo(entry.Element("msg").Value)
                   });

---

关于信息，后面的“C#Depth”章节详细介绍了这一领域；它非常详细地描述了语法转换规则。+1给出了一个漂亮、清晰的答案，解释了原理，而不仅仅是具体示例的解决方案。Bart De Smet编写了一个方便的翻译，在方法和查询语法之间进行转换。

select C

.Select(entry=>C)

var logQuery = xDoc.Descendants("logentry")
               .Where(entry=>
                          entry.Element("author").Value.ToLower().Contains(matchText) ||
                          entry.Element("msg").Value.ToLower().Contains(matchText) ||
                          entry.Element("paths").Value.ToLower().Contains(matchText) ||
                          entry.Element("revision").Value.ToLower().Contains(matchText))
                .Select(entry=>new
                   {
                       Revision = entry.Attribute("revision").Value,
                       Author = entry.Element("author").Value,
                       CR = LogFormatter.FormatCR(entry.Element("msg").Value),
                       Date = LogFormatter.FormatDate(entry.Element("date").Value),
                       Message = LogFormatter.FormatComment(entry.Element("msg").Value),
                       ET = LogFormatter.FormatET(entry.Element("msg").Value),
                       MergeFrom = LogFormatter.FormatMergeFrom(entry.Element("msg").Value),
                       MergeTo = LogFormatter.FormatMergeTo(entry.Element("msg").Value)
                   });