Eval Expression.NET Discover How to Execute Dynamic LINQ

Definition

The Eval-Expression.NET library allows evaluating, compiling and executing C# code and expression at runtime.

It supports nearly everything including:

• Anonymous Type
• Extension Methods
• Generic Type
• Lambda Expression
• String Interpolation

Eval.Execute

Execute a C# expression and return the result.

int result = Eval.Execute<int>("X + Y", new { X = 1, Y = 2});

int result = Eval.Execute<int>(@"
    var list = new List<int>() { 1, 2, 3, 4, 5 };
    var filter = list.Where(x => x < 4);
    return filter.Sum(x => x);");

Learn more

Eval.Compile

Compile a C# expression and return a delegate.

// using Z.Expressions; // Don't forget to include this.

string code = "Price * Quantity";
var compiled = Eval.Compile<Func<OrderItem, decimal>>(code);

decimal totals = 0;
foreach(var order in orders)
{
    totals += compiled(order);
}

Learn more

Eval Dynamic LINQ

The Eval-Expression.NET library makes it possible and very easy by allowing dynamic query with the same syntax as LINQ.

Everything you do in LINQ, you can do it dynamically with this library. The C# dynamic expression is not interpreted but compiled into LINQ expression.

var list = new List<int>() { 1, 2, 3, 4, 5 };

var linqStatic  = list.Where(x => x > 2);
var linqDynamic = list.Where(x => "x > 2");

Learn more

Requirements

Entity Framework Version

• All versions are supported.

Learn more about the library