原创 c# - 漢字數字,阿拉伯數字,相互轉換

using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace DesignPatterns.Chines

原创 c# - CancellationToken Demo

using System; using System.Threading; using System.Threading.Tasks; namespace TaskCancellationTest { class Progra

原创 c# - Task again

using System; using System.Threading.Tasks; namespace TestTask { class Program { static void Main(str

原创 EntityFramwork Core - Reverse Engineering

基於Db Model->Update數據庫Schema: 應用migration1: 1. 修改你的Db Model 2. 執行:Add-Migration migration1 -Context "MyDbContext" 3. 執行:

原创 c# - entityframework core - switch databases

更換數據庫之後,如果舊的Migrations導致數據庫錯誤,可按照以下步驟重新生成Migrations: 1. 刪除所有existing migrations(包含:DataContextModelSnapshot), 直接文件刪除就可以

原创 Some commands

------------New projects------------ 1. dotnet new classlib -n Infrastructure 2. dotnet sln add Infrastructure 3. dotn

原创 SQL - northwind, pub 示例數據庫 腳本

原文鏈接:https://github.com/cjlee/northwind https://github.com/cjlee/northwind

原创 Python - why we use if __name__ == "__main__" in python code.

原文鏈接:https://stackoverflow.com/questions/419163/what-does-if-name-main-do https://stackoverflow.c

原创 Javascript - Object Utility

原文鏈接:http://shop.oreilly.com/product/9780596805531.do /* * Copy the enumerable properties of p t

原创 Javascript frameworks

1. Babel JS:Convert new version js to lower version js. 2. ESLint: Js 語法檢查。 3. PWA Vue: A Progressive Web Application (

原创 Javascript falsy values

The falsy values are:false, null, undefined, 0, -0, NaN, and "". All other values, including all objects, are truthy -F

原创 SQL - 關聯分組 left join 取 top 1

原文鏈接:https://stackoverflow.com/questions/7363930/how-to-select-a-single-record-in-a-left-join --

原创 c# - 線程 Thread AutoResetEvent 與 ManualResetEvent

using System; using System.IO; using System.Text; using System.Threading; namespace ThreadingDemo { /// <summary>

原创 你的賬號是否被泄露了?

有兩個網站可以查詢你拿自己郵箱註冊的賬號是否被泄露了,自查一下: https://haveibeenpwned.com/ https://monitor.firefox.com/

原创 c# - double 與 decimal

Double與Decimal的區別如下: class Program { static void Main(string[] args) { double a = 0.3