LINQ(Language Integrated Query)是一种用于查询和操作各种数据源的统一编程模型。它提供了一种简洁、直观的方式来查询和操作数据,无论是集合、数据库、XML文档还是其他数据源。 在LINQ中使用AND连接可以通过以下两种方式实现: 查询表达式方式: 代码语言:txt 复制 var result = from item in collection where item.Pro...
现在我们使用linq来实现上边的代码: publicvoidTest(stringa,stringb,stringc,stringd) { QueryContext query =newQueryContext(); varq =fromuinquery.Users selectu; if(!string.IsNullOrEmpty(a)) { q = q.Where(p => p.name == a); } if(!string.IsNullOrEmpty(b)) { q = q.Where(p => p....
sql语句的想要实现的内容如下,重点关注where后面的条件部分:select...from...where(Test.id =3and Test.name ="N3") or (Test.id =4and Test.name ="N4") linq方式的动态实现如下:varpredicate = PredicateBuilder.False<Test>();foreach(varkeywordinsearchKeywords) {intnTemp =keyword.id;stringsTemp =...
现在我们使用linq来实现上边的代码: 代码语言:javascript 复制 publicvoidTest(string a,string b,string c,string d){QueryContext query=newQueryContext();varq=from uinquery.Users select u;if(!string.IsNullOrEmpty(a)){q=q.Where(p=>p.name==a);}if(!string.IsNullOrEmpty(b)){q=q.Where(p=>p....
I have a sql data source that is populating a dropdown. I am trying to do it with linq. Here is the query SELECT sUserFullName, MIN(nUserID) AS nUserID FROM UserMaster WHERE nssiCorpID = 6036 AND (nDatabaseID <> 0) AND (nStatusMasterID = 200) ...
A while back, mostly for fun, I implemented something similar, but purely in LINQ: public static readonly Func<string, int?> TryParseInt = ((Func<int, string, int?>)((seed, value) => int.TryParse(value, out seed) ? seed : (int?)null)).Curry()(default(int)); Where Curry is ...
SomeOther.SomeInteger, Others = from b in a.SomeOthers select b.SomeDate.Month, More = from c in a.MoreOthers select c.SomeOther.SomeDate.Day }As with every ToWhatever helper within NeinLinq, ToNullsafe can be called wherever within the LINQ query chain....
Office Development: OBA Solution Patterns In The Real World Editor's Note: Too Many Swimming Pools Toolbox: Easy Web Debugging, Extending Reflector, and More CLR Inside Out: Improving Application Startup Performance Data Points: Standard Query Operators with LINQ Advanced Basics: Office 2007 Files ...
C# and Linq --> Operator '>=' cannot be applied to operands of type 'int' and 'System.Linq.IQueryable<int?> C# How to retrieve values from the last row in a DataTable C# How to update a data base with a DataSet? C# Parameterized Query with null values ...
To test a LINQ query, type it into the top-right pane. You can enter a LINQ query directly or type in the C# or Visual Basic® code that executes a LINQ query. When writing and testing LINQ to SQL queries, you can select the database from the upper-left ...