為何在react的表單中加了onsubmit之后表單還是會跳轉(zhuǎn)

import React, { Component } from 'react';
import { Form, FormGroup, Col, Button, Checkbox, FormControl, ControlLabel} from 'react-bootstrap';
import '../CSS/login.css'

class Login extends Component{


    handleClick(){
        alert("false");
        return false;
    }
    render(){
        return (
            <Form horizontal className="login" method="post" action="http://localhost:8080/regester.do">
                <FormGroup controlId="formHorizontalEmail">
                      <Col componentClass={ControlLabel} sm={2}>
                        郵件
                      </Col>
                      <Col sm={10}>
                        <FormControl type="phonenumber" name="username" placeholder="請輸入您的手機號碼" />
                      </Col>
                </FormGroup>

                <FormGroup controlId="formHorizontalPassword">
                  <Col componentClass={ControlLabel} sm={2}>
                    密碼
                  </Col>
                  <Col sm={10}>
                    <FormControl type="password" name="password" placeholder="請輸入您的密碼" />
                  </Col>
                </FormGroup>

                <FormGroup>
                  <Col smOffset={2} sm={10}>
                    <Checkbox>記住我</Checkbox>
                  </Col>
                </FormGroup>

                <FormGroup>
                  <Col smOffset={2} sm={10}>
                    <Button type="submit" onClick = {this.handleClick}>
                      登錄
                    </Button>
                  </Col>
                </FormGroup>
            </Form>
        );
    }

}
export default Login

無論是在Button上加onClick,還是在Form上加onSubmit，最后還是會跳轉(zhuǎn)到action,這個該如何解決