« LINQKit » : différence entre les versions
De Banane Atomic
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* [https://github.com/scottksmith95/LINQKit LINQKit] on GitHub | * [https://github.com/scottksmith95/LINQKit LINQKit] on GitHub | ||
= AsExpandable = | = [https://github.com/scottksmith95/LINQKit#plugging-expressions-into-entitysets--entitycollections-the-solution AsExpandable] = | ||
<kode lang='csharp'> | <kode lang='csharp'> | ||
Expression<Func<User, bool>> expression = x => x.Name.EndsWith("2"); | Expression<Func<User, bool>> expression = x => x.Name.EndsWith("2"); | ||
Version du 14 mars 2021 à 12:08
Links
- LINQKit on GitHub
AsExpandable
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Expression<Func<User, bool>> expression = x => x.Name.EndsWith("2");
context.Users.Where(expression); // works fine !
// as x.Users is not a IQueryable, Any cannot take an Expression but a Func
// so we need to use Compile to get Func from Expression
context.Groups.Where(x => x.Users.Where(expression.Compile())); // Entity Framework will throw an exception
// solution: use AsExpandable
context.Groups.AsExpandable().Where(x => x.Users.Any(expression.Compile()));
// Compile never actually runs; AsExpandable will strip out the call to Compile and substitute it with a correct expression tree
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Installation
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dotnet add package LinqKit.Microsoft.EntityFrameworkCore |
