Assume you have products and categories. A client says that it is necessary to use other business processes for the categories with the rating value higher than 50. You have a solid experience and you understand that tomorrow this value may be different – 127.37. As you want to avoid this situation, you write the code in the following way:
Hangfire is a multi-threaded and scalable task scheduler built on client-server architecture on .NET stack (Task Parallel Library and Reflection) with the intermediate storage in a database. There is a free LGPL v3 version with open source. In this article, we are going to explore how to use Hangfire.
When adding or modifying a large number of records (10³ and more), the Entity Framework performance is far from perfect. The reasons are architectural peculiarities of the framework, and non-optimality of the generated SQL. Leaping ahead, I can reveal that saving data through a bypass of the context significantly minimizes the execution time. (more…)
Entity Framework 6 was and still remains a ‘workhorse’ for data access in corporate .NET-based applications primarily because of its stability, low barrier of entry and wide renown. Therefore, I hope this article will still be useful. (more…)
In the previous article, we have reviewed a general concept of implementing a minimum set of required modifications that include overriding the Object.Equals(Object) and Object.GetHashCode() methods in order to compare class objects by value on a standard .NET framework.
Let’s consider the implementation features of the Object.Equals(Object) method so that it meets the following documentation requirement:
x.Equals(y) returns the same value as y.Equals(x).
The string data type is one of the most significant data types in any programming language. You can hardly write a useful program without it. Nevertheless, many developers do not know certain aspects of this type. Therefore, let’s consider these aspects.
Representation of strings in memory
In .Net, strings are located according to the BSTR (Basic string or binary string) rule. This method of string data representation is used in COM (the word ‘basic’ originates from the Visual Basic programming language in which it was initially used). As we know, PWSZ (Pointer to Wide-character String, Zero-terminated) is used in C/C++ for representation of strings. With such location in memory, a null-terminated is located in the end of a string. This terminator allows to determine the end of the string. The string length in PWSZ is limited only by a volume of free space. (more…)
This article is devoted to the GetHashCode method and the GetHashCode implementation in the .NET Framework. The article also discusses the different behavior of the method for reference types and value types. The topic is quite interesting and any self-respecting .NET developer needs to know it. So let’s go!
What’s stored in reference-type objects apart from their field?
Let’s begin our story with learning what is stored in reference-type objects in addition to their fields.
Each reference type object has the so-called header, which consists of two fields: a pointer to the type of the object (MethodTablePointer), as well as a synchronization index (SyncBlockIndex).
It is known, a computer can operate numbers with a limited number of bits. As a rule, we are accustomed to work with the 32-bit and 64-bit integers. On the .Net platform, the Int32 (int) and Int64 (long) types correspond to these integers.
But what to do if we need to represent, for instance, number 29! = 8841761993739701954543616000000? Such number won’t fit both 32-bit and 64-bit data types. Long arithmetic is designed specifically for working with such big numbers.
In computing technology, long arithmetic implies operations (addition, multiplication, subtraction, division, raising to a power etc.) with numbers, the bitness of which exceeds the length word of the given computer. These operations are implemented not by hardware but by software with the help of basic hardware for working with small-order numbers.
As all developers, I often need to measure the execution time of my own (and not only my own) code. When I was a beginning programmer, I used the DateTime structure for this purpose. Time have passed and I learned about the Stopwatch class and began using it extensively. I think most of you had a similar experience. It’s not like I didn’t wonder about how Stopwatch works, at that time, it was simply enough for me to know that Stopwatch measures the elapsed time more precise than DateTime. Now the time has come to explain to myself as well as to the readers how the Stopwatch class actually works and clarify its pros and cons in comparison with DateTime.
GDI leak (or, simply the usage of too many GDI objects) is one of the most common problems. It eventually causes rendering problems, errors, and/or performance problems. The article describes how we debug this problem.
In 2016, when most programs are executed in sandboxes wherefrom even the most incompetent developer cannot harm the system, I am amazed to face the problem I will speak about in this article. Frankly speaking, I hoped that this problem had gone forever together with Win32Api. Nevertheless, I faced it. Before that, I just heard horror stories about it from old more experienced developers. (more…)