The difference between watch and methods in vue

In Vue, watch is used to respond to data changes and trigger callback functions; methods is used to execute user-defined methods, which can be called from any component method or template, and is mainly used to perform calculations, process data, or trigger operations. .

##The difference between watch and methods in vue

Main difference:

watch and methods are both Vue.js features used to respond to data changes, but they have different functions and uses :

watch :

Monitor changes in specific data.
• When the monitored data changes, the callback function is triggered.
• Mainly used to respond to data changes and perform corresponding operations.

methods:

Contains user-defined methods.
• Can be called from any component method or template.
• Mainly used to perform calculations, process data or trigger operations.

Detailed explanation:

Function:

• watch Used for Respond to data changes, and methods are used to perform operations.
• watch is declarative, while methods is imperative.

Grammar:

watch:

watch: {
  someProperty: {
    handler: function (val, oldVal) {
      // 数据变化时调用的函数
    },
    // 可选选项
    immediate: true,  // 立即触发
    deep: true,       // 深度监视
  },
}

methods：

methods: {
  someMethod: function () {
    // 执行的操作
  },
}

Usage:

• watch Usually used to respond to changes in component state or external data .
• methods For any operations or calculations that need to be performed in the component.

Best Practice:

Use
• watch to monitor data changes and take appropriate actions.
Use
• methods to perform operations and calculations that need to be called explicitly.
Avoid data manipulation in
• methods as it violates Vue.js's reactive system.

The above is the detailed content of The difference between watch and methods in vue. For more information, please follow other related articles on the PHP Chinese website!