How to use Lambda in LINQ select statement

Question

I am trying to select stores using a lambda function and converting the result to a SelectListItem so I can render it   However it is throwing a  Type of Expression in Select Clause is Incorrect  error   IEnumerable lt SelectListItem gt  stores       from store in database Stores     where store CompanyID    curCompany ID     select  s   gt  new SelectListItem   Value   s ID  Text   s Name     ViewBag storeSelector   stores    What am I doing wrong   EDIT   Also  how do I convert Int to String in this situation   The following does not work   select  s   gt  new SelectListItem   Value   s ID ToString    Text   s Name     select  s   gt  new SelectListItem   Value   s ID       Text   s Name       EDIT 2   Figure out the Int to String conversion   It is so typical of Microsoft to forget to include an int2string conversion function   Here is the actual workaround everyone is using  with fully working syntax   select new SelectListItem   Value   SqlFunctions StringConvert  double store ID   Text   store Name      To call this situation absurd is an understatement

User · Accepted Answer

using LINQ query expression   IEnumerable lt SelectListItem gt  stores           from store in database Stores         where store CompanyID    curCompany ID         select new SelectListItem   Value   store Name  Text   store ID      ViewBag storeSelector   stores    or using LINQ extension methods with lambda expressions   IEnumerable lt SelectListItem gt  stores   database Stores          Where store   gt  store CompanyID    curCompany ID           Select store   gt  new SelectListItem   Value   store Name  Text   store ID       ViewBag storeSelector   stores

User · Answer

You appear to be trying to mix query expression syntax and  normal  lambda expression syntax  You can either use   IEnumerable lt SelectListItem gt  stores           from store in database Stores         where store CompanyID    curCompany ID         select new SelectListItem   Value   store Name  Text   store ID   ViewBag storeSelector   stores    Or   IEnumerable lt SelectListItem gt  stores   database Stores          Where store   gt  store CompanyID    curCompany ID           Select s   gt  new SelectListItem   Value   s Name  Text   s ID    ViewBag storeSelector   stores    You can t mix the two like you re trying to

User · Answer

Lambda Expression result   var storesList   context Stores Select x   gt  new   Value  x name Text  x ID    ToList

User · Answer

Why not just use all Lambda syntax   database Stores Where s   gt  s CompanyID    curCompany ID                  Select s   gt  new SelectListItem                                             Value   s Name                         Text   s ID

User · Answer

Using Lambda expressions    If we don t have a specific class to bind the result    var stores   context Stores Select x   gt  new   x id  x name  x city    ToList     If we have a specific class then we need to bind the result with it   List lt SelectListItem gt  stores   context Stores Select x   gt  new SelectListItem   Id   x id  Name   x name  City   x city    ToList       Using simple LINQ expressions    If we don t have a specific class to bind the result   var stores    from a in context Stores select new   x id  x name  x city    ToList     If we have a specific class then we need to bind the result with it   List lt SelectListItem gt  stores    from a in context Stores select new SelectListItem  Id   x id  Name   x name  City   x city    ToList

[c#] How to use Lambda in LINQ select statement

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