Let’s talk about examples of common writing methods

Ensure that a class has only one instance and provide a global access point to the instance. ——"Design Pattern" The concept of singleton mode is very simple. The following uses C# language as an example to list the advantages and disadvantages of common singleton writing methods. 1. Simple implementation of public sealed class Singleton {         static Singleton instance = null;        public void Show() {

1. Analysis of Singleton Pattern and Common Writing Methods (Design Pattern 01)

##Introduction: The concept of singleton pattern is very simple. The following uses C# language as an example to list the advantages and disadvantages of common singleton writing methods.

2. Mysql database condition judgment query statement common writing instructions

Introduction: Everyone knows that only Stored procedures only appeared in MySQL 5. For these usages, if we want to use if else while in SQL, we have to use stored procedures or functions to instantiate them. mysql DELIMITER // mysql CREATE FUNCTION myFunction (quantity INT(10)) RETURNS INT(10)

3. Five forms of MYSQL subquery

Introduction: MySQL has supported the subquery function since version 4.1. Before this version, you can use join to write a table query instead, but it is not recommended to write this, it is quite troublesome. Several common ways of writing mysql subqueries: select * from xxx where col=[ any | all ]( select * from xxxx); This syntax can be divided into ways of writing with keywords and without keywords. When

4. js object-oriented writing method_javascript skills

Introduction: This article mainly introduces four common js object-oriented methods The writing method also introduces the relevant content about this. Interested friends can refer to it

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