Can LINQ Queries Be Dynamically Generated from XML Data Without Recompilation?

Dynamically Generating LINQ Queries Without Recompilation

In scenarios where query parameters are sourced from dynamically updated external data, the need arises to generate LINQ queries without recompiling source code. Consider an object like SomeObject with numerous properties.

Is it feasible to create new LINQ queries dynamically by extracting criteria from an XML structure stored in a database?

For example:

var result = from i in someObj
             where 
             //XML requests Name = 'Bob'...so append this where clause
             name = 'Bob'

Solution Using Expression Trees

Employing expression trees provides a viable solution:

var param = Expression.Parameter(typeof(SomeObject), "p");
var exp = Expression.Lambda<Func<SomeObject, bool>>(
    Expression.Equal(
        Expression.Property(param, "Name"),
        Expression.Constant("Bob")
    ),
    param
);
var query = someObj.Where(exp);

Although this approach is considerably more complex, it offers a solution in specific scenarios where dynamic query generation is necessary.

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