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Custom verifier Basic syntax: xxx(params:AbstractControl):{[key:string]}:any{ renturn null; } The type of the incoming parameter is AbstractControl, which is the common parent class of FormGroup, FormControl and FormArray. The incoming parameter declares what object type the validator is used for (the three mentioned above) The return v ...

order Before learning service, we should understand what the "service" is used for. In fact, this service is just like the "service" in real life, such as: hairdressing service, foot washing service So what are the services of AngularJS? In AngularJS, a service is a function or object that can be used in yo ...

First, briefly explain the role of lazy loading: As the name implies, laziness means that resources that need to be loaded are not loaded the first time, but are loaded when the page needs to be used, usually to improve the efficiency of loading the first page. Here is a simple example of the basic use of lazy loading ...

html code: When the input departs from the change event, the touchUpdateImg method will be called. The file object will be passed in and the imgsmall property will be displayed. The file object will be read through the FileReader object. I used apply to monitor. I didn't use apply to monitor before. When I didn't use ...

We often use paging to display data when we do projects. The principle is very simple: each time we click (next / last) a page, we send a request to the background to obtain relevant JSON data. What I'm demonstrating here is that every time I request, I will pass two parameters (pageSize – data to be displayed on ...

The processing of Android return key in ionic 3 learning About provider Understand the provider of ionic3 provider is a concept defined by ionic itself, similar to our service on angular. There are some similarities and differences between the two. Contrast: Difference technology Commands used file name Route ...

5.vins_estimator Basically, most of the functions in VINS are under this package, including IMU data processing (front end), initialization (I think it may belong to front end), sliding window (back end), nonlinear optimization (back end), key frame selection (part of content) (front end). When I firs ...

In the learning part of attitude control, multi rotor attitude control is taken as an example.1. Overall process Attitude control is mainly divided into several parts: Attitude error angle calculation = > target angular velocity calculation = > angular velocity PID This part focuses on the calcula ...

Today, I encountered a front-end problem while learning the paging plug-in of angularjs. During the debugging of Google browser developer mode, I found that each click of paging refresh button would trigger two background requests, and ajax sent two requests to the background. This is a disgusting and uncomfortable thing for obsessive-compulsiv ...

Detailed introduction of angular file upload Angular file upload is a lightweight AngularJS file upload tool. It is designed for the file API Polyfill which does not support browser, and uses HTML5 to upload files directly. Online demo Characteristic Support upload progress, cancel or abort when uploading, support file drag ( ...