Home Web Front-end JS Tutorial What is the difference between wx:for and wx:for-item

What is the difference between wx:for and wx:for-item

Apr 20, 2018 pm 02:33 PM
the difference

This time I will bring you the difference between wx:for and wx:for-item, what are the precautions when using wx:for and wx:for-item, the following is a practical case, one Get up and take a look.

wx:for="{{list}}" is used to loop the array, and list is the array namewx:for-item=" items" is used to define the variable of each element during a loop. If it is a

one-dimensional array

, loop it out as follows:

In the above code, item is the alias of list.

If it is a two-dimensional or even

multi-dimensional array

, loop as follows:

is equivalent to

<view wx:for="{{list}}" wx:for-item="xxx"></view>
Copy after login
Copy after login

Remember: wx:for is a loop array , wx:for-item is to assign an alias to the list

The following are several incorrect uses, please use them with caution:

1. Use wx:for-item directly, so the loop will not come out List

<view wx:for-item="{{list}}">
{{index}} {{item.name}}
</view>
Copy after login
Copy after login

2. Use wx:for-item with caution in sub-loops

<view wx:for="{{parentList}}">
 {{item.id}}
 <view wx:for-item="{{item.childList}}" wx:for-item="items">
 {{items.name}}{{items.account}}
 </view>
Copy after login
Copy after login

Correct usage of wx:for and wx:for-item in WeChat applet

wx :for="{{list}}" is used to loop the array, and list is the array name wx:for-item="items" is used to define the variables of each element during the loop

If it is a one-dimensional array, it is looped out as follows:

<view wx:for="{{list}}">
{{index}} {{item.name}}
</view>
Copy after login
Copy after login

In the above code, item is the alias of list.

If it is a two-dimensional or even multi-dimensional array, loop as follows:

<view wx:for="{{parentList}}">
{{item.id}}
<view wx:for="{{item.childList}}" wx:for-item="items">
{{items.name}}{{item.account}}
</view>
</view>
for (var i = 0 ; i < list.length; i++) {
var xxx = list[i];
}
Copy after login
Copy after login

is equivalent to

<view wx:for="{{list}}" wx:for-item="xxx"></view>
Copy after login
Copy after login

Remember: wx:for is a loop array, wx:for-item That is to assign an alias to the list

The following are several incorrect uses, please use them with caution:

1. Use wx:for-item directly, so that the list cannot be looped

<view wx:for-item="{{list}}">
{{index}} {{item.name}}
</view>
Copy after login
Copy after login

2. Use wx:for-item with caution in sub-loops

<view wx:for="{{parentList}}">
 {{item.id}}
 <view wx:for-item="{{item.childList}}" wx:for-item="items">
 {{items.name}}{{items.account}}
 </view>
Copy after login
Copy after login

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Recommended reading:

Angular parent component calls the child component in detail


Instructions for newbies to vue

The above is the detailed content of What is the difference between wx:for and wx:for-item. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

What are the basic requirements for c language functions What are the basic requirements for c language functions Apr 03, 2025 pm 10:06 PM

C language functions are the basis for code modularization and program building. They consist of declarations (function headers) and definitions (function bodies). C language uses values ​​to pass parameters by default, but external variables can also be modified using address pass. Functions can have or have no return value, and the return value type must be consistent with the declaration. Function naming should be clear and easy to understand, using camel or underscore nomenclature. Follow the single responsibility principle and keep the function simplicity to improve maintainability and readability.

How to set password protection for export PDF on PS How to set password protection for export PDF on PS Apr 06, 2025 pm 04:45 PM

Export password-protected PDF in Photoshop: Open the image file. Click "File"&gt; "Export"&gt; "Export as PDF". Set the "Security" option and enter the same password twice. Click "Export" to generate a PDF file.

The difference between H5 and mini-programs and APPs The difference between H5 and mini-programs and APPs Apr 06, 2025 am 10:42 AM

H5. The main difference between mini programs and APP is: technical architecture: H5 is based on web technology, and mini programs and APP are independent applications. Experience and functions: H5 is light and easy to use, with limited functions; mini programs are lightweight and have good interactiveness; APPs are powerful and have smooth experience. Compatibility: H5 is cross-platform compatible, applets and APPs are restricted by the platform. Development cost: H5 has low development cost, medium mini programs, and highest APP. Applicable scenarios: H5 is suitable for information display, applets are suitable for lightweight applications, and APPs are suitable for complex functions.

Concept of c language function Concept of c language function Apr 03, 2025 pm 10:09 PM

C language functions are reusable code blocks. They receive input, perform operations, and return results, which modularly improves reusability and reduces complexity. The internal mechanism of the function includes parameter passing, function execution, and return values. The entire process involves optimization such as function inline. A good function is written following the principle of single responsibility, small number of parameters, naming specifications, and error handling. Pointers combined with functions can achieve more powerful functions, such as modifying external variable values. Function pointers pass functions as parameters or store addresses, and are used to implement dynamic calls to functions. Understanding function features and techniques is the key to writing efficient, maintainable, and easy to understand C programs.

Why do you need to call Vue.use(VueRouter) in the index.js file under the router folder? Why do you need to call Vue.use(VueRouter) in the index.js file under the router folder? Apr 05, 2025 pm 01:03 PM

The necessity of registering VueRouter in the index.js file under the router folder When developing Vue applications, you often encounter problems with routing configuration. Special...

What are the differences and connections between c and c#? What are the differences and connections between c and c#? Apr 03, 2025 pm 10:36 PM

Although C and C# have similarities, they are completely different: C is a process-oriented, manual memory management, and platform-dependent language used for system programming; C# is an object-oriented, garbage collection, and platform-independent language used for desktop, web application and game development.

How to use XPath to search from a specified DOM node in JavaScript? How to use XPath to search from a specified DOM node in JavaScript? Apr 04, 2025 pm 11:15 PM

Detailed explanation of XPath search method under DOM nodes In JavaScript, we often need to find specific nodes from the DOM tree based on XPath expressions. If you need to...

What are the different ways of promoting H5 and mini programs? What are the different ways of promoting H5 and mini programs? Apr 06, 2025 am 11:03 AM

There are differences in the promotion methods of H5 and mini programs: platform dependence: H5 depends on the browser, and mini programs rely on specific platforms (such as WeChat). User experience: The H5 experience is poor, and the mini program provides a smooth experience similar to native applications. Communication method: H5 is spread through links, and mini programs are shared or searched through the platform. H5 promotion methods: social sharing, email marketing, QR code, SEO, paid advertising. Mini program promotion methods: platform promotion, social sharing, offline promotion, ASO, cooperation with other platforms.

See all articles