如何訪問一個變量或其它函數內部函數的值

Question

我有發揮它有一個承諾，我想在其他功能使用

Submit: function (e) { 
     e.preventDefault(); 

     var email = this.refs.email.value; 
     var pass = this.refs.pass.value; 

     if (email && pass !== '') { 
      const auth = firebase.auth(); 
      const promise = auth.signInWithEmailAndPassword(email, pass); 
      promise.catch(e => { console.log(e.message) }); 
      promise.then(() => { 
       console.log('Logged in'); 
      }) 

     } 
    } 

現在我想用這個e.message對象，其值我的另一個功能樓下里面：

renderError: function() { 
        if (error) { 
         <Error custom{//here i want to use that e.message}/> 
    } 
} 

Answer 1

就像你說的，因爲該方法屬於同一類的Submit您可以通過this指它的...

class LoginForm { 
    submit() { 
    let 
     email = 'test@test.com', 
     pass = '1235' 
    ; 


    return firebase 
     .auth() 
     .signInWithEmailAndPassword(email, pass) 
     .then(
     this.renderSuccess.bind(this), 
     this.renderError.bind(this) 
    ); 
    } 

    renderError(error) { console.log('error', error); } 
    renderError(response) { console.log('success', response); } 
}