Pass Parameter on Linq Query

Question

Is it possible to pass the parameter after the period on a LINQ Query?

For example on this code:

objResultFinal = objResultFinal.OrderByDescending(x => x.[iwanttopassparameterhere]).ToList();

Is that possible? I want to declare after the "x." the string that I want to query.

What do you mean by passing a parameter? Do you mean accessing a property? — Maor Veitsman, Oct 03 '16 at 09:02
Yes accessing the property by passing it as parameter. Example: string strToPass = "myProperty" Then on LINQ Query: x => x.strToPass Is that possible? I want to dynamically query on LINQ and I am not sure what property is to filter yet. — Willy David Jr, Oct 03 '16 at 09:05
This is not a valid syntax: `x.[iwanttopassparameterhere]`. What are you trying to do ? — Zein Makki, Oct 03 '16 at 09:05
If you're quering the database then check this answer: http://stackoverflow.com/a/7265354/3185569 . If you're querying in-memory list then: http://stackoverflow.com/a/7265394/3185569 — Zein Makki, Oct 03 '16 at 09:17

score 1 · Accepted Answer · edited Oct 03 '16 at 09:21

1

objResultFinal.OrderByDescending(s => s.GetType().GetProperty("PropertyName").GetValue(s, null));

edited Oct 03 '16 at 09:21

Fabjan

13,050
3
22
49

answered Oct 03 '16 at 09:13

Radim Drtílek

246
2
7

score 1 · Answer 2 · answered Oct 03 '16 at 09:22

1

Maybe this can be done using dynamic LINQ as below -

objResultFinal.OrderBy(passYourParameterHere).ToList();

answered Oct 03 '16 at 09:22

R Jain

416
3
9

score 0 · Answer 3 · answered Oct 03 '16 at 09:20

0

Your list is that of type object? You'd either have to cast it first or use reflection.

Using casting:

var sortedList = objectList.Cast<Email>().OrderByDescending(item => item.EmailAddress).ToList();

answered Oct 03 '16 at 09:20

ThePerplexedOne

2,860
13
29

Eldho · Answer 4 · 2016-10-03T09:30:24.053

var list = new List<MyClass>();

list.Add(new MyClass { Name = "V" });
list.Add(new MyClass { Name = "B" });
list.Add(new MyClass { Name = "A" });
list.Add(new MyClass { Name = "C" });

//Create expression here, IF YOU ARE SORTING ON STRING PROPERTY KEEP KEY AS STRING OR CHANGE TO RESPECTIVE DATA TYPE
Func<MyClass,string> expression = s=>s.Name;

var ordered = list.OrderByDescending(expression).ToList();

The Class Object

class MyClass
{
    public string Name { get; set; }
}

Pass Parameter on Linq Query

4 Answers4