Javascript pre-increment vs post-increment vs increment-equal

Test on:Node v.14.17.3Pre-increment – increment then read the variable, example:++jPost-increment – read the variable then increment, example:k++Increment-equal – increment then read the variable, example:l+=1Test code: console.log('--- j'); let j = 1; console.log(++j); console.log(j); console.log('--- k'); let k = 1; console.log(k++); console.log(k); console.log('--- l'); let l =…

Tested on:.Net Framework 4.8 Calculate working days (Monday, Tuesday, Wednesday, Thursday and Friday) given 2 dates. For example:– Monday 8/2/2021 to Wednesday 8/4/2021 is 2 days – In this case, 8/4/2021 is excluded because the time is not specified there in .Net it is assigned to 12:00 AM.– Monday 8/2/2021 12 PM to Wednesday 8/4/2021 12 PM is 2 days.– Friday 8/6/2021 12 PM to Tuesday 8/10/2021…

Dynamic Azure Data Table Query

Tested on:Node.js 14.17.3Typescript 4.3.5@azure/data-tables 12.1.0Continuing on previous post.To use dynamic query, we can replace the filter parameter with inline variable. For example: const propertyName = 'PartitionKey'; const propertyValue = 'Stanford'; const tableClient = azTableService.getTableClient('Student'); const results = tableClient.listEntities({ queryOptions: { filter:…

Turn Off VSCode Intellisense

Press CTRL + SHIFT + P to open Command Palette.Type/choose “Preferences: Open Settings (JSON)”.Add or modify following settings in proper JSON format. { "editor.suggestOnTriggerCharacters": false, "editor.quickSuggestions": { "other": false, "comments": false, "strings": false } } References: https://code.visualstudio.com/docs/editor/intellisense#_customizing-intellisense

Null/Undefined Check in Typescript

Tested on:Node.js 14.17.3Typescript 4.3.5ConclusionTo check whether an object is null or undefined, use either: if (a == null) { } or if (a) { } Few gotcha with both approaches:1. Both approaches will not cover the case when let a = '' or let a: string = ''.2. The second approach will fail when a is unexpectedly boolean value, ie: let a = false. I personally prefer more explicit approach and…

Azure Data Table Query In Typescript

Tested on:Node.js 14.17.3Typescript 4.3.5@azure/data-tables 12.1.0There are not many resources when it comes to querying Azure Storage’s Table.This is official sample code from Microsoft:https://github.com/Azure/azure-sdk-for-js/blob/main/sdk/tables/data-tables/samples/v12/typescript/src/queryEntities.tsIt provides some example but not much.This post will attempt to provide more extensive…

The UnboundLocalError in Python could be caused by many reasons.I encountered this error when doing the following:1. Declare and assign global variable.2. Try to re-assign the global variable inside a function.3. Get UnboundLocalError.The solution is to use global keyword before the variable name in the function where the variable will be used. This is to indicate it as a global variable,…

Module ‘foo’ can only be default-imported using the ‘allowSyntheticDefaultImports’

Happened when you tried to import Commonjs module into ES6 module codebase.For example in Javascript we import like this:exports = fooModuleWhich is equivalent of this in Typescript (but not compliant with ES6/ES2015 specs):import * as foo from 'foo'Solution is to enable esModuleInterop in tsconfig.json. { "compilerOptions": { "module": "commonjs", "esModuleInterop":…

ERR! Unexpected end of JSON input while parsing near ‘…’

There are many causes of this error. But the core issue is the same, corrupted NPM packages.Here are possible solutions:– Run npm clear cache --force– Delete node_modules folder and rebuild.– Uninstall and reinstall Angular/CLI.– Uninstall and reinstall…

Jupiter Kernel location in both Windows/MacOs system. Useful when need to delete them.Unix:System: /usr/share/jupyter/kernels/usr/local/share/jupyter/kernelsEnv: {sys.prefix}/share/jupyter/kernelsUser:~/.local/share/jupyter/kernels (Linux)~/Library/Jupyter/kernels (Mac)Windows:System: %PROGRAMDATA%\jupyter\kernelsUser:…

Tested on:.Net Framework 4.8Quick way to run background task utilizing hosting environment’s process. var worker = new SomeWorker(); HostingEnvironment.QueueBackgroundWorkItem(ct => worker.StartProcess()); The SomeWorker() is a method that we want to run in the background.Keep in mind, because the background process is run in the host, if the host is restarted (ie: IIS) the background process…

MacOs Default Git Editor

Tested on:MacOs Big SurSteps to set default git editor in MacOs:1. Open Terminal.2. Run the following command in Terminal: git config --global core.editor "code --wait"

Free Python Practice Book

Python Practice Book

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What’s the Difference Between Width/Height in CSS and Width/Height HTML attributes?

I save you time if you prefer not to read this one. Presentational attributes (HTML attributes) have weaker (or lesser priority) compare to CSS attribute of the same function.

23 lesser known VS Code Shortcuts as GIF

You probably have seen a lot of similar posts, but this explains the shortcut in …

Advanced Features with Azure Service Bus

High level overview of advanced features, from Session & FIFO, Auto Forwarding, Scheduling, Deferred, Duplicate detection to high availability and disaster recovery.

Strangler pattern

If you ask me, I think it’s not much of an architecture pattern, but more of migration strategy. Especially useful to migrate from legacy to modern applicati…

Think Python

PDF version: http://www.greenteapress.com/thinkpython/thinkpython.pdf

First of the Week Reading List

How to use npx: the npm package runner

There’s so much to say about `npx`, but essentially, it allows you to run package (think of the cli tool that comes with a package) without installing it globally, or without installing the package at all!

Microsoft: We want you to learn Python programming language for free

Learn Python for free! But obviously, you probably already expect th…