多列不区分大小写的组

本文介绍了多列不区分大小写的组的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

无论如何，有没有做类似的事情的LINQ2SQL查询:

Is there anyway to do a LINQ2SQL query doing something similar to this:

var result = source.GroupBy(a => new { a.Column1, a.Column2 });

或

var result = from s in source group s by new { s.Column1, s.Column2 } into c select new { Column1 = c.Key.Column1, Column2 = c.Key.Column2 };

但是忽略分组列内容的大小写吗?

but with ignoring the case of the contents of the grouped columns?

推荐答案

您可以将StringComparer.InvariantCultureIgnoreCase传递给GroupBy扩展方法.

You can pass StringComparer.InvariantCultureIgnoreCase to the GroupBy extension method.

var result = source.GroupBy(a => new { a.Column1, a.Column2 }, StringComparer.InvariantCultureIgnoreCase);

或者您也可以按照 Hamlet Hakobyan 的建议在每个字段上使用ToUpperInvariant.我建议使用ToUpperInvariant或ToUpper而不是ToLower或ToLowerInvariant，因为它已针对程序比较进行了优化.

Or you can use ToUpperInvariant on each field as suggested by Hamlet Hakobyan on comment. I recommend ToUpperInvariant or ToUpper rather than ToLower or ToLowerInvariant because it is optimized for programmatic comparison purpose.