c# - Generic DbUpdateConcurrencyException Handler EF Core 2.0 -


i have working solution handling dbupdateconcurrencyexception user can presented values exist in database compared own posted input when concurrency token (byte[] rowversion) doesn't match.

catch (dbupdateconcurrencyexception ex) {     var entry = ex.entries.single();     var clientvalues = (applicationuser)entry.entity;     var databaseentry = entry.getdatabasevalues();     if (databaseentry == null)     {         modelstate.addmodelerror(string.empty,             "unable save changes. subject user deleted user.");     }     else     {         var databasevalues = (applicationuser)databaseentry.toobject();          if (databasevalues.firstmidname != clientvalues.firstmidname)             modelstate.addmodelerror("firstmidname", "current value: "                 + databasevalues.firstmidname);         if (databasevalues.lastname != clientvalues.lastname)             modelstate.addmodelerror("lastname", "current value: "                 + databasevalues.lastname);          // etc.. every property can changed          modelstate.addmodelerror(string.empty, "the record attempted edit "             + "was modified user after got original value. "             + "edit operation canceled , current values in database "             + "have been displayed. if still want edit record, click "             + "the save button again. otherwise click list hyperlink.");         requestmodel.rowversion = databasevalues.rowversion;         modelstate.remove("rowversion");     } }

i can see kind of concurrency handling being used on of edit actions across project i've been trying come generic solution.

is possible handle exception entity , iterate on properties perform value comparison between posted values , database values without needing explicitly declare entity or property names?

this (wishful thinking) example of i've been trying achieve can't property info of available entities:

var entry = ex.entries.single(); var clientvalues = entry.entity; var databaseentry = entry.getdatabasevalues(); var databasevalues = databaseentry.toobject();  foreach(var property in databasevalues.metadata.properties) {     var dbvalue = databasevalues.property(property.name).currentvalue;     var clientvalue = clientvalues.property(property.name).currentvalue      if(dbvalue != clientvalue)         modelstate.addmodelerror(property.name, "current value: " + dbvalue); }


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