« LINQKit » : différence entre les versions
De Banane Atomic
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// solution: use AsExpandable | // solution: use AsExpandable | ||
context.Groups.AsExpandable().Where(x => x.Users.Any(expression.Compile())); | 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 | |||
</kode> | </kode> | ||
Version du 14 mars 2021 à 11:13
Links
- LINQKit on GitHub
AsExpandable
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 |
Installation
dotnet add package LinqKit.Microsoft.EntityFrameworkCore |