Programmer Think

Proxy Proxy is used to create a proxy for an object to modify the default behavior of some operations. It can be understood as setting up a layer of "interception" in front of the target object. External access to the object must first pass through this layer of interception. Therefore, it provides a mechanism for us to filter and re ...

Review of knowledge points: Function: Formal and argument, unequal Short circuit assignment String splicing (string splicing is used when many values are returned) Scope!!!!!! Global, local and scope are relative (the child function can access the variables of the parent function) Formal parameter: it is essentially a local variable pre ...

1, Factory function 1 when the component executes_ When the render function is converted to a virtual VNode, the createComponent() function will be executed when a component is encountered, as follows: function createComponent ( //Line 4184 creates the component Vnode Ctor, //Ctor: constructor o ...

JavaScript from getting started to mastering video through train:         [1-200] JavaScript video tutorial, from introduction to mastery, with more cases of practice, easy to understand!         [201-300] JavaScript video tutorial, from introduction to mastery, with more cases of practice, easy to understand! JavaScript process control stat ...

1. Create a String object var strOb = new String("abcefg"); ​ var strOb = String("abcefg"); ​ var strOb = "abcefg"; Summary: any data type, as long as it is enclosed in quotation marks, is a string object 2. String properties stringObj.length (String length) 3. Method 3.1) substring position indexOf(string,[index]) / / returns the first ...

vue3 implements the response expression through Proxy+Reflect, and vue2 implements it through definePropertyProxyWhat is ProxyProxy is a class added in ES6 to represent proxy.If we want to listen to the operation process of the object, we can first create a proxy object, and then all operations on the object are completed by the proxy object. T ...

Find: 1. Search by selector: in the future, if the elements are hidden deeply and scattered, the search conditions become very complex, you can search by selector   (1) . find only one element that meets the requirements    a. var an element object = any parent element. querySelector("selector")    & ...

promise introduction Promise is a solution for asynchronous programming, which is more reasonable than traditional solutions (callback functions and events). What is synchronization? After the current call is issued, subsequent code cannot be executed before the result is received, and the subsequent code is always online waiting, and synchr ...

1, window object 1.BOM   Browse object model     In fact, it is some ability to operate the browser             What can we do:             - Get some browser related information (window size)             - Operate the browser for ...

(1) Promise Promise means promise. (it's something that will happen in the future) (1) What is promise? In terms of purpose: (1) promise is mainly used for asynchronous computing. (2) You can queue asynchronous operations, execute them in the desired order, and return the expected results. (3) promise can be passed and manipulated between ob ...