c# - Unable to create a constant value of type . Only primitive types or enumeration types are supported in this context -



c# - Unable to create a constant value of type . Only primitive types or enumeration types are supported in this context -

i have next method generic check exist,

public virtual bool checkexist(t entity) { var context = new etrdataentities(); iqueryable<t> dbquery = context.set<t>(); if (dbquery.any(e => e == entity)) { homecoming true; } homecoming false; }

however returns exception:

unable create constant value of type . primitive types or enumeration types supported in context.

please advice,

many thanks,

try changing code taking in type t next method name, this:

public virtual bool checkexist<t>(t entity) { var context = new etriksdataentities(); iqueryable<t> dbquery = context.set<t>(); if (dbquery.any(e => e == entity)) { homecoming true; } homecoming false; }

you may want restrict type classes only, this:

public virtual bool checkexist<t>(t entity) t : class { var context = new etriksdataentities(); iqueryable<t> dbquery = context.set<t>(); if (dbquery.any(e => e == entity)) { homecoming true; } homecoming false; }

c# entity-framework

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