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Copyright notice Original author: brother Gu's younger brotherAuthor blog address: http://blog.csdn.net/lfdfhl Event handling overview In Vue, it is very convenient to handle events, such as click events, mouse over events, etc. Main steps: 1. Define the function in the methods of the Vue instance.2. Specify the event type and its corres ...

Knowledge points of ecarts data visualization (I) 1. Use steps (1) Import the echorts.js file (2) Prepare a box to present the chart (3) Initialize the ecarts instance object (parameters, dom elements, which determine the final rendering position of the chart) var mCharts = echarts.init(document.querySelector('div')) (4) Prepare configur ...

Vue learning (I) - preliminary understanding Source: PC personal blog 1. Front rear relationship Vue is a progressive framework for building user interfaces, which can be applied layer by layer from bottom to topMVVM mode Model: model layer, representing jsView: view layer, DOMViewModel: middleware connecting views and data. Vue.js is t ...

For a high-performance react component, it is important to reduce redrawing and rearrangement, server rendering, and so on. In a react application, the logic is organized as a react component, which splits the UI into separate, reusable components. Then the component performance optimization is maliciously considered from the perspective of co ...

Promise.resolve The Promise.resolve() method returns a promise object parsed with the given value. If the value is a promise, the promise will be returned; If the value is thenable (i.e. with "then" method), the returned promise will "follow" the thenable object and adopt its final state. const thenable = { then(onFullfi ...

1. Declare multiple variables //Conventional writing let x； let y = 20； //Abbreviation let x，y = 20； 2. Assign values to multiple variables Use array deconstruction assignment //Conventional writing let a，b，c； a = 5； b = 8； c = 10； //Abbreviation let [a,b,c] = [5,8,10] 3. Proper use of ternary operators //Conventional writing let ma ...

1. Pre-resolution 1. Variable Pre-parsing and Function Pre-parsing JavaScript code is executed by the JavaScript parser in the browser. The JavaScript parser runs JavaScript code in two steps: pre-parsing and code execution. Pre-parsing: In the current scope, variables with var and function declarations are declared or defined in memory ...

1, Comparison of Vue, angular and react three mainstream frameworks 1. Compared with angular api is simple, quick to start, and low learning cost;Angel uses two-way binding, and Vue also supports two-way binding. However, it is a one-way data flow, and the data is transmitted from the parent component to the child component in one directionIn ...

Preface Lifecycle of components and associated hook functions text Lifecycle of components: The life cycle is the entire process from creation of a component to not running unloaded from a page. There are many functions that run throughout the life cycle, which are hook functions. Only class components have a life cycle. Hook function at cre ...

Environment construction of JavaScript Development environment: webstorm, hbulider Running environment: chrome browser code Knowledge 1 Several ways of writing JavaScript 1 2 3 4. Realize the display of data in the page 5 prompt Popup 5. Define variables // var a =1; global variable // var a =1; // alert(typeof (a) ...