Divide by zero error resolved

src/component/App.js

@@ -4,21 +4,51 @@ import ButtonPanel from "./ButtonPanel";
 import calculate from "../logic/calculate";
 import "./App.css";
 
+
 export default class App extends React.Component {
   state = {
     total: null,
     next: null,
     operation: null,
   };
 
+  constructor(props){
+    super(props);
+    this.inputRef = React.createRef();    //ref to focus master div
+  }
+
+  componentDidMount(){
+    this.inputRef.current.focus();    //focusing master div to listen keyboard press
+  }
+
+  keyHandler = (e) => {
+    console.log(e.key);
+    if(e.key == 0 || e.key == 1 || e.key == 2 || e.key == 3 || e.key == 4 || e.key == 5 || e.key == 6 || e.key == 7 || e.key == 7 || e.key == 8 || e.key == 9
+      || e.key == '+' || e.key == '-' || e.key == "%" || e.key == "."){
+            this.setState(calculate(this.state, e.key));
+      }
+      else if(e.key == "Enter"){
+          this.setState(calculate(this.state, "="));
+      }
+      else if(e.key == "*"){
+        this.setState(calculate(this.state, 'x'));
+      }
+      else if(e.key == "/"){
+        this.setState(calculate(this.state, '÷'));
+      }
+
+  }
+
   handleClick = buttonName => {
     this.setState(calculate(this.state, buttonName));
   };
 
+
+
   render() {
     return (
-      <div className="component-app">
-        <Display value={this.state.next || this.state.total || "0"} />
+      <div className="component-app" ref={this.inputRef} onKeyDown={this.keyHandler} tabIndex="0">
+        <Display value={this.state.next || this.state.total || "0"}/>
         <ButtonPanel clickHandler={this.handleClick} />
       </div>
     );

src/component/ButtonPanel.js

@@ -13,6 +13,7 @@ export default class ButtonPanel extends React.Component {
     this.props.clickHandler(buttonName);
   };
 
+
   render() {
     return (
       <div className="component-button-panel">

src/logic/operate.js

@@ -13,7 +13,7 @@ export default function operate(numberOne, numberTwo, operation) {
     return one.times(two).toString();
   }
   if (operation === "÷") {
-    if (two === "0") {
+    if (two.cmp(0) == 0) {      //Used cmp function to compare the value
       alert("Divide by 0 error");
       return "0";
     } else {