improve performance : shoudComponentUpdate, PureComponent

react_webgame/main/RenderTest.jsx

@@ -0,0 +1,35 @@
+import React, { PureComponent } from 'react';
+
+class Test extends PureComponent {
+    state = {
+        counter: 0,
+        string: 'hello',
+        number: 1,
+        boolean: true,
+        object: {},
+        array: [],
+    };
+
+    // shouldComponentUpdate(nextProps, nextState, nextContext) {
+    //     if(this.state.counter !== nextState.counter) {
+    //         return true;
+    //     }
+    //     return false;
+    // }
+
+    onClick = () => {
+        this.setState({
+            array: [...this.state.array, 1],
+        });
+    }
+
+    render() {
+        console.log('렌더링', this.state);
+        return (
+            <div>
+                <button onClick={this.onClick}>클릭</button>
+            </div>
+        )
+    }
+}
+export default Test;

react_webgame/main/client.jsx

@@ -1,6 +1,7 @@
 import React from 'react';
 import ReactDom from 'react-dom';
 
-import NumberBaseball from './NumberBaseball';
+import Test from './RenderTest';
 
-ReactDom.render(<NumberBaseball />, document.querySelector('#root'));
+
+ReactDom.render(<Test />, document.querySelector('#root'));