ios - 代码永远不会执行错误

Question

Xcode 显示代码永远不会执行的警告，但我不明白为什么。谁能启发我？ (错误发生在完成处理程序内部的内部 if 和 else 语句中，用于两个验证语句)

- (IBAction)siginButtonPressed:(UIButton *)sender
{
    if (isLogin)
{
    [[FIRAuth auth] signInWithEmail:_usernameTextField.text
                           password:_passwordTextField.text
                         completion:^(FIRUser *user, NSError *error)
         {
             if (FIRAuthErrorCodeUserNotFound)
             {
                 _credentialVerification.text = @"Invalid Credentials";
                 _entryValidation.text = @"An account with the listed credentials was not found, please proceed to registration screen via the navigation bar at the top of the applications user interface";
             }
             else
             {
 /*(Warning 1)*/ _credentialVerification.text = @"Valid Credentials";
                 [self performSegueWithIdentifier:@"toMainScreen" sender:self];
             }
         }

     ];
}
else
{
    [[FIRAuth auth] createUserWithEmail:_usernameTextField.text
                               password:_passwordTextField.text
                             completion:^(FIRUser *_Nullable user, NSError *_Nullable error)
         {
             if (FIRAuthErrorCodeInvalidEmail)
             {
                 _credentialVerification.text = @"Invalid Email";
             }
             else
             {

 /*(Warning 2)*/ _entryValidation.text = @"Account creation was succesful, please proceed to the login screen via the navigation bar at the top of the applications user interface";
             }
         }

     ];
}

编辑:

- (IBAction)siginButtonPressed:(UIButton *)sender
{
if (isLogin)
{
    [[FIRAuth auth] signInWithEmail:_usernameTextField.text
                           password:_passwordTextField.text
                         completion:^(FIRUser *user, NSError *error)
                         {
                             if (error.code == FIRAuthErrorCodeUserNotFound)
                             {
                                 _credentialVerification.text = @"Invalid Credentials";
                                 _entryValidation.text = @"An account with the listed credentials was not found, please proceed to registration screen via the navigation bar at the top of the applications user interface";
                             }
                             else
                             {
                                 _credentialVerification.text = @"Valid Credentials";
                                 [self performSegueWithIdentifier:@"toMainScreen" sender:self];
                             }
                         }
     ];
}
else
{
    [[FIRAuth auth] createUserWithEmail:_usernameTextField.text
                               password:_passwordTextField.text
                             completion:^(FIRUser *_Nullable user, NSError *_Nullable error)
                             {
                                 if (error.code == FIRAuthErrorCodeInvalidEmail)
                                 {
                                     _credentialVerification.text = @"Invalid Email";
                                 }
                                 else
                                 {
                                     _entryValidation.text = @"Account creation was succesful, please proceed to the login screen via the navigation bar at the top of the applications user interface";
                                 }
                             }
     ];
}
}

Answer 1

您的代码中的问题是您正在检查枚举，因为枚举的值不为零，因此它将始终为真并且不会进入 else 部分，因此您需要更改两个 if 语句中的条件以检查错误像这样的代码(我不确定语法但希望你能明白)

if (error.code == FIRAuthErrorCodeUserNotFound)
if (error.code == FIRAuthErrorCodeInvalidEmail)

更新

修改你的 if else 语句如下:

if (error) {
       NSLog(@"%@", error)
}else {
       //code when there is no error    
}