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Original posted at:

The site has been down for a couple of days for me so I thought of making a copy of it.

The .NET team released Preview 2 of .NET Core 2.0 as well as a newer build of Visual Studio Preview 15.3 (Preview 3) yesterday:

Here are the downloads for .NET Core 2.0 Preview 2:

One of the big changes for .NET Core 2.0 is the addition of more than 20,000 new APIs to the framework.  They are expanding the API list so it’s easier to migrate older apps to .NET Core.   They say 2.0 will support 70% of all existing packages in the Nuget repo.

Selenium with .NET Core


Last November (2016), I blogged about how the Selenium team had not yet added support for .NET Core but a community member had forked the code and created a new Nuget package with support.  At this time the Selenium team still hasn’t added official support for .NET Core but they may not need to now.

I’m happy to confirm .NET Core 2.0 Preview 2 can successfully run Selenium tests using the official Selenium Nuget packages with no additional changes or unofficial extensions.  I have not performed extensive testing by any means but basic UI automation with Selenium definitely works now with the latest preview.

Here is a working solution:

Core 2.0 compatibility

Its great to see a very tangible example of a pre-existing Nuget package that broke with .NET Core 1.0 now working with 2.0.  This goes to show that Microsoft is listening to customers and adjusting their plans accordingly.

I have actually been testing Selenium with each new .NET Core preview that is released and each seemed to get a bit closer to working.  .NET Core 2.0 Preview 1, for example, had an issue with finding the System.Security.Permissions API.  But that was resolved with Preview 2.

Microsoft provides a very cool API search tool which makes it very easy to research what APIs are available in each version of .NET:



Microsoft is getting closer to a final release of .NET Core 2.0 (target for this fall last I heard) and making good on their promise to increase backwards compatibility of the framework.  This will make it far easier for developers to port their legacy code to .NET Core and gain all its benefits (cross-plat, speed, modular, flexible deployment, open source).

Post originally appeared at:

Please refer the thread for more discussion, this is for reference purpose only.


The Visual Studio debugger is a magical beast that can save you loads of time while finding and fixing issues in your application. It is chock-full of tools that can make debugging easier… if you know they exist, and where to find them! Let’s look at 7 lesser known goodies you can use to help you #SuperChargeYourDebugging.

1. Click to Set Next Statement

Many of you may know about the context menu item Set Next Statement (Ctrl+Shift+F10) that moves the yellow arrow (the instruction pointer) to the target line of code. You may also know that you grab and drag the yellow arrow up and down in the gutter to move it. What you probably didn’t know is that as of Visual Studio 2017 version 15,3 Preview there is an even easier way to target a line and Set Next Statement.

1. Hover over the line of code where you want to move the yellow arrow.

2. Hold the CTRL key and notice the Run to Click (Run execution to here) glyph changes into the Set Next Statement glyph.

3. Click on that glyph and the yellow arrow will move to that line.

4. This line will be the next statement to execute when taking a step or pressing Continue (F5).

Set Next Statement

2. Break when a value changes

Have you been in a situation while debugging where you inspect an object’s property at one breakpoint and by the time you get to the next breakpoint that property has changed unexpectedly. You can set a breakpoint on the setter in the class, but this breaks for every instance of the object type! What if you only care about one problematic instance? When debugging C++ code, Data Breakpoints can help you out. If you are debugging managed code, you can use Make Object ID plus a Conditional Breakpoint to narrow your search for the problem area.

  1. When you get to a breakpoint with the interesting instance right click on the object and select Make Object ID. This gives you a handle to that object in memory, referenced by “$1”.
  2. Go to the setter of the property you care about and add a condition to the breakpoint,
    “this == $1”
  3. Press Continue (F5) and now you will break in the setter when that property changes for that instance.
  4. Look at the Call Stack and double click on the previous frame. This will take you to the line of code that is changing the property for this specific instance of the object.

Break when a value changes

Note: The object ID refers to the object’s address in memory and consequently will change with every new debug session. So, if you need to restart debugging, be sure to right click and re-create the object ID. The handle ($1) won’t change, so you can leave your breakpoint as is between debug sessions.

3. Reattach to Process

This is a true time-saver introduced in Visual Stuido 2017 that many of you have yet to discover. It is extremely helpful when you are working on a project where you need to use “Attach to Process” but you find yourself consistently attaching to the same thing session after session.

  1. Start from the Attach to Process dialog (Ctrl+Alt+P) and select the process or processes that you want to debug and click “Attach”.
  2. When you terminate that debugging session go to the Debug menu on the toolbar.
  3. Click Reattach to Process or use shortcut key (Shift +Alt+P).

reattach to process

For more in-depth details about Reattach to Process check out this blog post.

4. Show Threads in Source

Debugging a multithreaded application is rarely easy, but when you can see in the editor what lines of code each thread in currently on, it gets a lot better.

  1. In the debugger toolbar, toggle the button “Show Threads in Source”
  2. A glyph will appear in the breakpoint gutter next to each line of code where at least one thread is currently stopped.
  3. Hover over the thread marker icon to see the thread ids and names for all threads currently stopped on that line of code.
  4. Right click on the thread to see available actions you can perform like freezing and switching the active thread.

Show Threads in Source

Note: This functionality comes with some performance overhead and can feel like it slows down debugging. We recommend turning it off when you aren’t actively using it.

5. Step through one single thread without jumping around

How often are you debugging multithreaded code, when you hit your first breakpoint, take a step, and then suddenly you are stopped with the yellow arrow on another thread? The unexpected behavior comes from the breakpoint still being set and consequently being hit. By default, the debugger will stop on a breakpoint any time it is hit. This means that when you take a step, all threads are allowed to run, and one of your running threads hit this breakpoint before the step completes on your current thread. Next time you get in this situation try this:

  1. Disable or delete the breakpoint that has been hit by the new thread the debugger switched to.
  2. Press Continue (F5)
  3. Observe how your first initial step on that first thread completes and now is the active debugging context.
  4. Since your breakpoints are deleted or disabled, you can continue stepping on that single thread without interruption.

Step through one single thread without jumping around

6. Debug.ListCallStacks -allThreads

When there are lots of threads, there can be lots of call stacks to figure out. You may need to inspect all of them to get a good picture of what state your application is in. You can always see a visual representation of the call stacks for each thread by using the Parallel Stacks window (Debug/Windows/ Parallel Stacks). You can also see a text based, copy/paste-able version of the call stack for each thread using the Command window.

  1. Open the Command Window (View/Other Windows/Command Window).
  2. Type “Debug.ListCallStacks – allThreads
  3. You can also use the popular WinDBG command “~*k
  4. See how each thread is listed with its call stack displayed in the window.

List Call Stacks

7. Side Effect Free Function Evaluation “, nse”

Have you ever innocently typed an expression into the Watch window or Immediate window, then had to deal with the side effects of a debug session where you changed the state of the application without meaning to? Often this can happen when trying to evaluate an expression that calls a function in your program and it causes side effects (state changes to the program without running the actual application). While this may be okay if you know what functions will be called, what if you’re not sure? Here is a way to evaluate expressions in C# without the risk of side effects corrupting your program.

  1. You can add “, nse” (stands for “No Side Effects”) after any expression you type into the Watch window or Immediate window.
  2. This will use a sandbox of sorts that will interpret the expression without causing any side effects.
  3. If the expression can’t be interpreted and can only be resolved by an evaluation, it will show you an error in the window.
  4. If you are sure that you want to evaluate it anyway, remove the “, nse” modifier and try again.

NSE - No Side Effects

The original post appeared here:

Please visit the original website for more discussion, this is for reference purpose only.


using System;
using System.Collections;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;

public partial class UserDefinedFunctions
FillRowMethodName = "FillRow_Multi",
TableDefinition = "item nvarchar(4000)"
public static IEnumerator SplitString_Multi(
[SqlFacet(MaxSize = -1)]
SqlChars Input,
[SqlFacet(MaxSize = 255)]
SqlChars Delimiter
return (
(Input.IsNull || Delimiter.IsNull) ?
new SplitStringMulti(new char[0], new char[0]) :
new SplitStringMulti(Input.Value, Delimiter.Value));

public static void FillRow_Multi(object obj, out SqlString item)
item = new SqlString((string)obj);

public class SplitStringMulti : IEnumerator
public SplitStringMulti(char[] TheString, char[] Delimiter)
theString = TheString;
stringLen = TheString.Length;
delimiter = Delimiter;
delimiterLen = (byte)(Delimiter.Length);
isSingleCharDelim = (delimiterLen == 1);

lastPos = 0;
nextPos = delimiterLen * -1;

#region IEnumerator Members

public object Current
return new string(theString, lastPos, nextPos - lastPos);

public bool MoveNext()
if (nextPos >= stringLen)
return false;
lastPos = nextPos + delimiterLen;

for (int i = lastPos; i < stringLen; i++)
bool matches = true;

//Optimize for single-character delimiters
if (isSingleCharDelim)
if (theString[i] != delimiter[0])
matches = false;
for (byte j = 0; j < delimiterLen; j++)
if (((i + j) >= stringLen) || (theString[i + j] != delimiter[j]))
matches = false;

if (matches)
nextPos = i;

//Deal with consecutive delimiters
if ((nextPos - lastPos) > 0)
return true;
i += (delimiterLen-1);
lastPos += delimiterLen;

lastPos = nextPos + delimiterLen;
nextPos = stringLen;

if ((nextPos - lastPos) > 0)
return true;
return false;

public void Reset()
lastPos = 0;
nextPos = delimiterLen * -1;


private int lastPos;
private int nextPos;

private readonly char[] theString;
private readonly char[] delimiter;
private readonly int stringLen;
private readonly byte delimiterLen;
private readonly bool isSingleCharDelim;

Found this interesting article on

Most people tend to think MVC and web api are the same thing. Well not really!


While developing your web application using MVC, many developers got confused when to use Web API, since MVC framework can also return JSON data by using JsonResult and can also handle simple AJAX requests. In previous article, I have explained the Difference between WCF and Web API and WCF REST and Web Service and when to use Web API over others services. In this article, you will learn when to use Web API with MVC.

Asp.Net Web API VS Asp.Net MVC

  1. Asp.Net MVC is used to create web applications that returns both views and data but Asp.Net Web API is used to create full blown HTTP services with easy and simple way that returns only data not view.
  2. Web API helps to build REST-ful services over the .NET Framework and it also support content-negotiation(it’s about deciding the best response format data that could be acceptable by the client. it could be JSON,XML,ATOM or other formatted data), self hosting which are not in MVC.
  3. Web API also takes care of returning data in particular format like JSON,XML or any other based upon the Accept header in the request and you don’t worry about that. MVC only return data in JSON format using JsonResult.
  4. In Web API the request are mapped to the actions based on HTTP verbs but in MVC it is mapped to actions name.
  5. Asp.Net Web API is new framework and part of the core ASP.NET framework. The model binding, filters, routing and others MVC features exist in Web API are different from MVC and exists in the new System.Web.Httpassembly. In MVC, these featues exist with in System.Web.Mvc. Hence Web API can also be used with Asp.Net and as a stand alone service layer.
  6. You can mix Web API and MVC controller in a single project to handle advanced AJAX requests which may return data in JSON, XML or any others format and building a full blown HTTP service. Typically, this will be called Web API self hosting.
  7. When you have mixed MVC and Web API controller and you want to implement the authorization then you have to create two filters one for MVC and another for Web API since boths are different.
  8. Moreover, Web API is light weight architecture and except the web application it can also be used with smart phone apps.
What do you think?