من این برنامه رو اجرا کردم ولی روی خط 5 پیغام خطا 

 System.NullReferenceException: Object reference not set to an instance of an object. 

رو میگیرم .

اگر امکانش هست میتونید پروژه این مثال رو بگذارید.

ممنون

در حالاتی که از AutoMapper در یک عبارت LINQ استفاده بشه در صورت وجود مواردی همچون FullName در مقصد خطای "Object reference not set to an instance of an object" رو throw می‌کنه.

آیا شما هم با چنین مشکلی برخورد کردید؟

These are the customer-reported issues addressed in 15.8.5:

• Debugger tooltip does not expand in Xamarin.iOS debugging session.
• Debugger won't let me leave execution point (Android).
• After updating to 15.8.1, data tip does not show when debugging.
• Debugger data tip does not expand [Editor].
• Exception:MSB0001: Internal MSBuild Error: Already registered for build-time.
• Wrong path to resource in manifest for ClickOnce after upgrading to VS 15.8.1.
• ClickOnce Manifest error in 15.8.
• ClickOnce Publish is missing certain references.
• ClickOnce: Language file copied to wrong location.
• Reference missing in the ClickOnce publish folder.
• Compiling non-.NET SDK style F# projects results in an internal MSBuild error unless MSBuild parallelism is set to 1.
• F# is not NGEN'd in Visual Studio.
• F# deploys the FSharp.Core 4.5.0.0 binary in the 4.4.3.0 location.

Details of What's New in 15.8.5

Visual Studio Tools for Xamarin

Visual Studio Tools for Xamarin now supports Xcode 10, which allows you to build and debug apps for iOS 12, tvOS 12, and watchOS 5. See how to get ready for iOS 12 and our introduction to iOS 12 for more details on the new features available. 

A class should have only one reason to change.

 

Dynamically change the site theme to the selected theme 

This release contains the following improvements and enhancements:

• This release now installs Java™ Development Kit 8, Update 181 (JDK version 8u181). 

These are the customer-reported issues addressed in 15.7.6:

• Visual C++ Redistributable 2017 does not report the install state in a specific registry location.
• In 15.7 users may see extensions load without all of their assets and cause VS to crash. This has been addressed for 15.7.6.
• Visual Studio 2017 version 15.7.5 crashes when opening a solution. 

Here is a partial list of the C# coding standards my team uses and advocates. Most of these are industry-wide conventions and thus using them will ensure that your code is easily readable by people who are not you.  

Visual Studio Code doesn't support solution files, whereas Visual Studio does. In Visual Studio we use solution files to link multiple projects together, and at first I thought that this was going to be a deal breaker for Visual Studio Code - but it's not at all. Many people aren't aware that Visual Studio Code, although lightweight, is a powerful editor that can do most of the things you need. 

Missing Features in Entity Framework Core
Here’s a brief summary of some of the features that were present in previous versions of Entity Framework (6.x) and were excluded (or are not yet implemented) in Entity Framework Core 2.0: 

Cisco has addressed a maximum severity vulnerability in its Application Centric Infrastructure (ACI) Multi-Site Orchestrator (MSO) that could allow an unauthenticated, remote attacker to bypass authentication on vulnerable devices.