Mail validity control

src/components/TestForm/index.tsx

@@ -26,17 +26,36 @@ export const Form: React.FC = () => {
   interface formData {
     email: string;
     password: string;
+    errors: Array<string>;
   }
 
   const defaultValues: formData = {
     email: '',
     password: '',
+    errors: [],
   };
   const [formValues, setFormValues] = useState<formData>(defaultValues);
 
+  const isEmailValid: any = () => {
+    /**
+     * The following is the RFC 5322 valid email regex
+     * Hinted from question https://stackoverflow.com/questions/201323/how-to-validate-an-email-address-using-a-regular-expression
+     * More on http://emailregex.com/
+     */
+    // eslint-disable-next-line
+    const VALID_EMAIL_REGEX = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
+    return VALID_EMAIL_REGEX.test(String(formValues.email).toLowerCase());
+  };
+
   const handleSubmit: any = (event: any) => {
     event.preventDefault();
-    console.log(formValues);
+    const errors: Array<string> = [];
+    if (!isEmailValid()) {
+      errors.push('email');
+      console.log('Email address not valid');
+    } else {
+      console.log(formValues);
+    }
   };
 
   const classes = useStyles();