Using string in place of property name (LINQ)

Question

I have been able to get the values from tables using linq.

var q=(from app in context.Applicant 
        where app.ApplicantName=="")

Now what I want is this:

 var q=(from app in context.Applicant 
        where app.stringIhave =="")  // so instead of column name I have string which has same name as column.

Is it possible to specify string in Select as this is not sure what I will get in each case, I need different data all the time.

Is it possible to do so? If no, then I will figure out something else. Update I have a GlobalString, which holds the column name of a table. So when I query that table, I only specify from string which column value I want to get:

var q=(from app in context.Applicants
       where app.ID==1013
       select GlobalString //which is specifying that I want to get value from which column, as column name is not fixed.
 //where GlobalString can have values like: app.FirstName..app.LastName etc

Update1:

var q = context.Applicants.Select("new(it.ApplicantFirstName as FirstName, it.ApplicantLastName as LastName)");

Error Message:

The query syntax is not valid. Near keyword 'AS'

Sergey Berezovskiy · Accepted Answer · 2013-12-20T07:50:00.467

2

You can use Dynamic Linq (available from NuGet) for that:

   var q = context.Applicant.Where(app.stringIhave + " = @0", "");

edited Dec 20 '13 at 07:50

answered Dec 20 '13 at 07:37

Sergey Berezovskiy

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i think you need add that `app` in your sample is not same that `app` in OP – Grundy Dec 20 '13 at 07:55
@ItiTyagi yep, you can pass string to `Select` too – Grundy Dec 20 '13 at 09:23
@ItiTyagi can you provide code what you try do, and what you whant get? – Grundy Dec 20 '13 at 09:55
1

@ItiTyagi code above works just fine. Maybe you have specified wrong property name or value to filter. For your edit code will look like `context.Applicants.Where("ID=@0", 1013).Select("PropertyName")` – Sergey Berezovskiy Dec 20 '13 at 10:35

score 0 · Answer 2 · answered Dec 20 '13 at 10:28

0

for select you can try something like this

var q = context.Applicant.Select("new(it.FirstName as FirstName, it.LastName as LastName)");

so you only need construct string for that format

answered Dec 20 '13 at 10:28

Grundy

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@ItiTyagi, do you can provide error message, and sample code what you tried? Also it sample work for `Dynamic Linq` only – Grundy Dec 20 '13 at 13:01
@ItiTyagi it strange, but try without as – Grundy Dec 20 '13 at 13:23
I tried my best, by shuffling syntax, but like this its not working. – Incredible Dec 20 '13 at 13:26
on new test project its work, possibly you can provide little more code or input data? – Grundy Dec 20 '13 at 13:31
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/43597/discussion-between-iti-tyagi-and-grundy) – Incredible Dec 20 '13 at 13:32
try select one column like `var q = context.Applicants.Select("ApplicantFirstName")` its work? – Grundy Dec 20 '13 at 14:09

Using string in place of property name (LINQ)

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