AngularJS – Directive 介紹篇
接續前面提到的關於產品展示頁面的製作，我們在HTML文件上面加入一個Add to Cart的按鈕，但是希望這個按鈕可以有條件性的顯示或隱藏，我們可以在該按鈕的HTML標籤中加入ng-show=”store.product.canPurchase”的屬性，這個屬性會去判斷在gem數列中canPurchase中的值是否為true，若不是則該按鈕不顯示於畫面上，反之則會顯示加入購物車（Add to Cart）的按鈕。
在這個案例中canPurchase就算是在數列中的顯示參數，其實這個參數並不是一定要叫canPurchase這個名稱，可以自行決定名稱，例如在馬老師製作的案例中，我就是利用buttonShow這樣的參數名稱，大家也可以在JS Bin上面看看這個案例的程式碼。
<!DOCTYPE html>
<html ng-app="store">
<head>
<meta name="description" content="AngularJS directivesExample 1">
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.2/angular.min.js"></script>
<meta charset="utf-8">
<title>AngularJS directivesExample 1</title>
</head>
<body>
<div ng-controller="StoreController as store">
<h1>{{ store.product.name }}</h1>
<h2>NT${{ store.product.price }}</h2>
<p>{{ store.product.description }}</p>
<button ng-show="store.product.buttonShow">加入購物車</button>
</div>
</body>
</html>
(function(){
var app = angular.module('store',[]);
app.controller('StoreController',function(){
this.product = item;
});
var item = {
name:"馬老師雲端研究室 滑鼠墊",
price:"350",
description:"有些人認為滑鼠墊就只是種簡單的產品。無非是將滑鼠放於上方並將之滑來拖去。 “表面”上來說確實如此（一語雙關）。但實際上，製造能帶來卓越遊戲體驗的滑鼠墊卻需要結合眾多科學、技術和工藝。身為遊戲滑鼠技術的世界領先者，對如何使滑鼠感測器高效運作我們獨樹一幟。運用專門知識來製造適合的滑鼠墊表面，讓滑鼠感測器得以作出高效而精確的反應。",
buttonShow: false
};
})();
另外還有一種資料顯示的手法，我們可以在gem數列中另外加入soldOut這個參數，而在div的HTML標籤中加入ng-show=”!store.product.soldOut”這樣的屬性，其中驚嘆號指的是不等於，所以這個屬性的意思即是當soldOut參數不等於true的時候要隱藏該div，也就是會隱藏所有的商品資訊。
不過這樣的表達方式並不是很直接，必須要做邏輯上的轉換，因為條件式是soldOut不等於true就顯示該商品，不是很容易搞懂，所以同樣的案例我們可以把HTML中的標籤的屬性改成ng-hide=”store.product.soldOut”，這樣一來我們只需要去看soldOut參數中的值是true或是false，如果賣完就不顯示；沒賣完就顯示，這是一個比較直覺的方法，透過JS Bin觀賞本案例的原始碼。
接下來看多項商品的製作方式，首先必須了解如何在Javascript的數列中加入多項商品的資料。
輸入了以上數列的資料後，在HTML的頁面上可以依下圖的方式呈現出多重商品的資訊，不過從以下的呈現方式可以看的出來，如果商品數量不僅僅是只有兩項，那頁面上面的HTML標籤就會過於複雜，所以下面的方法僅僅是讓大家了解邏輯的部分。
實際上呈現的方式可以參考下圖，是不是簡單多了，在JS Bin上面觀看。
接下來幫大家整理目前講解到的一些AngularJS的專有名稱說明：
- Directives（指示） – 在HTML中觸發Javascript行為的參數。
- Modules（模組） – 定義我們的應用程式。
- Controllers（控制器） – 定義我們應用程式該如運作。
- Expressions（表達式） – 我們的資料該如何的顯示在頁面上。
※以上截圖部分為AngularJS官方教學視訊，另有directive指令介紹的專頁。
I used to be able to find good info from your blog articles.
minocycline 100mg online: Ivermectin iver fast – stromectol 12mg
http://cytpremium.com/# cytotec pills buy online
Hi, I do believe this is an excellent web site. I stumbledupon it 😉 I am going to come back once again since I saved as a favorite it. Money and freedom is the best way to change, may you be rich and continue to guide others.
Aw, this was an exceptionally nice post. Taking the time and actual effort to produce a great article… but what can I say… I procrastinate a whole lot and never seem to get anything done.
Thanks for thr great article!
Hello there! I could have sworn I’ve been to this web site before but after browsing through some of the posts I realized it’s new to me. Nonetheless, I’m definitely delighted I came across it and I’ll be book-marking it and checking back often.
lisinopril1st: cheapest Lisinopril – cheapest Lisinopril
Lisinopril 1st lisinopril 40 mg india 3 lisinopril
Spot on with this write-up, I honestly think this website needs a great deal more attention. I’ll probably be back again to see more, thanks for the information.
You are so interesting! I do not think I’ve truly read something like that before. So good to discover somebody with some unique thoughts on this topic. Really.. thank you for starting this up. This website is one thing that is needed on the web, someone with a little originality.
https://cytpremium.com/# cytotec pills buy online
I blog quite often and I genuinely appreciate your content. Your article has really peaked my interest. I’m going to bookmark your site and keep checking for new details about once a week. I opted in for your RSS feed as well.
mexico pharmacies prescription drugs https://mexicanpharmgate.com/ mexican mail order pharmacies
I was able to find good information from your blog articles.
buy cytotec over the counter: cheapest cytotec – purchase cytotec
Fantastic entry. I found the content extremely helpful. Loved the manner you clarified all the points.
Excellent article. It gave tons of valuable details. I value the time you dedicated to compose this content.
гѓ—гѓ¬гѓ‰гѓ‹гѓійЂљиІ©гЃ§иІ·гЃ€гЃѕгЃ™гЃ‹ – г‚ўг‚ёг‚№гѓгѓћг‚¤г‚·гѓі гЃ®иіје…Ґ г‚ўг‚ёг‚№гѓгѓћг‚¤г‚·гѓійЂљиІ©гЃ§иІ·гЃ€гЃѕгЃ™гЃ‹
where to buy cheap clomid pill: clomid – can i purchase generic clomid without rx
prednisone 50 mg for sale: cheap prednisone – prednisone acetate
Aw, this was a very good post. Taking the time and actual effort to generate a really good article… but what can I say… I put things off a whole lot and don’t manage to get anything done.
how to buy amoxycillin: amoxil com pharm – amoxicillin order online no prescription
Genuinely liked this post. It offered a lot of useful insights. Fantastic effort on creating this.
Appreciated the insight in this entry. It’s highly detailed and full of useful details. Fantastic work!
where buy cheap clomid no prescription: can i order generic clomid for sale – where to get clomid price
where to buy amoxicillin over the counter: Amoxicillin Com Pharm – generic amoxicillin 500mg
Terrific article. It’s extremely clear and full of useful insight. Thanks for sharing this post.
Appreciated the information in this entry. It’s highly well-researched and full of beneficial information. Great work!
Terrific entry. It’s very well-written and packed with valuable insight. Thank you for sharing this content.