C#学习教程：LINQ to Entities无法识别方法’System.String Split（Char ）’方法

LINQ to Entities 不识别方法“System.String ToXX()”，因此该方法无法转换为存储表达式
这是因为LINQ语句最后都是要转为sql语句来执行的，当它转换后，发现sql语句中要执行的方法“XX”，并不是一个在数据库中的存储过程函数，也无法进行转换为存储表达式。
Entity Framework不支持String.Split 。 这只是因为SQL中没有等价物。

 

public List SearchByMultipleKeyword(string keywords) { string[] keyword = keywords.Split(','); var results = (from a in Entities.TblActivities where a.Keywords.Split(',').Any(p => keyword.Contains(p)) select a).ToList(); return results; } 

LINQ to Entities does not recognize the method 'System.String[] Split(Char[])' method, and this method cannot be translated into a store expression. 

绕过

 public List SearchByMultipleKeyword(string keywords) { string[] keywords = pKeywords.Split(','); var results = Entities.TblActivities.AsQueryable(); foreach(string k in keywords){ results = from a in results where a.Keywords.Contains(k) select a; } return results.ToList(); } 

var results = (from a in Entities.TblActivities select a).ToList(); //Results are now in memory results = results.Where(a => a.Keywords.Split(',').Any(p => keyword.Contains(p))).ToList(); //This uses LINQ-to-objects 
绕过

 public List SearchByMultipleKeyword(string keywords) { string[] keywordsSeparated = keywords.Split(','); var results = (from a in Entities.TblActivities where keywordsSeparated.Any(keyword => a.Keywords.Contains(keyword)) select a).ToList(); return results; } 

源文：
C#学习教程：LINQ to Entities无法识别方法’System.String Split（Char ）’方法，分享-猴子技术宅 (ssfiction.com)