\u9700\u8981 React 16.7.0 \u4ee5\u4e0a:<\/p>\n
\r\n\r\nimport React, {useState,useEffect} from 'react';\r\nimport ReactDOM from 'react-dom';\r\n\r\nlet histories = [];\r\n\r\nconst App = function(props){\r\n\t\r\n\tlet _style = {\r\n\t\ttextAlign: 'center',\r\n\t\tmargin: '100px',\r\n\t\tfontSize: '50px',\r\n\t\tlineHeight: '100px'\r\n\t}\r\n\t\r\n\tconst [counter,setCounter] = useState(10);\r\n\t\r\n\tuseEffect(() => {\r\n\t\thistories.push(counter);\r\n\t\tconsole.log(histories);\r\n\t},[counter]);\r\n\t\r\n\treturn (\r\n\t\t<div style={_style}>\r\n\t\t\t{counter}\r\n\t\t\t<br \/>\r\n\t\t\t<button onClick={() => {setCounter(counter + 1)}}>Increment<\/button>\r\n\t\t\t<button onClick={() => {setCounter(counter)}}>Just Kidding<\/button>\r\n\t\t\t<button onClick={() => {setCounter(counter - 1)}}>Decrement<\/button>\r\n\t\t<\/div>\r\n\t)\r\n}\r\n\r\n\r\nReactDOM.render(\r\n\t<App \/>\r\n\t,\r\n\tdocument.getElementById('root')\r\n);\r\n\r\n<\/pre>\nConsole Output:<\/p>\n
\r\n\r\nmain.js:21594 https:\/\/fb.me\/react-devtools\r\nmain.js:24846 [10]\r\nmain.js:24846 (2)\u00a0[10, 11]\r\nmain.js:24846 (3)\u00a0[10, 11, 12]\r\nmain.js:24846 (4)\u00a0[10, 11, 12, 11]\r\nmain.js:24846 (5)\u00a0[10, 11, 12, 11, 10]\r\nmain.js:24846 (6)\u00a0[10, 11, 12, 11, 10, 9]\r\nmain.js:24846 (7)\u00a0[10, 11, 12, 11, 10, 9, 10]\r\nmain.js:24846 (8)\u00a0[10, 11, 12, 11, 10, 9, 10, 11]\r\nmain.js:24846 (9)\u00a0[10, 11, 12, 11, 10, 9, 10, 11, 12]\r\nmain.js:24846 (10)\u00a0[10, 11, 12, 11, 10, 9, 10, 11, 12, 11]\r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"