动态LINQ在哪里查询

Question

I'm using dynamic LINQ to create a query from given columns the user selects for a given search.

eg simplified code ex:

var counter = 0;
var predicate = string.Empty;
foreach(var field in selectedFields)
{
    predicate += field + ".Contains(@" + counter + ") ||"; 
    // logical OR, without it the SQL generates AND
}    
predicate = predicate.Remove(predicate.LastIndexOf("||", 2));
query = query.Where(predicate, searchvalues);

This code generates the given SQL query

(([t0].[Field1] LIKE 'searchstring') OR ([t0].[Field2] LIKE 'searchstring'))

Which is correct, albeit what i want to do is be able to use wildcards, when i try to enter let's say, a percent character, the SQL generated is

(([t0].[field1] LIKE 'searchstring' ESCAPE '~') OR ([t0].[field2] LIKE 'searchstring' ESCAPE '~'))

Is there a way to use wildcards in the searchstring while using dynamic L2S?

Regards

Answer 1

You can try using .StartsWith || .EndsWith || .Contains .StartsWith || .EndsWith || .Contains

That might solve the problem.

Answer 2

Since you're using Linq to Sql then you can make use of the SqlMethods helper class.

One of the methods is Like which maps onto the SQL LIKE clause. If you need it, it is more flexible than using .StartsWith etc