Ios 目标-c NSURL认证存储和删除不起作用

我这里有一个方法，它是一个注销方法，可以清除由以下人员创建的会话：

NSURLCredential *credential = [NSURLCredential
                                   credentialWithUser:user
                                   password:password
                                   persistence:NSURLCredentialPersistenceForSession];

问题是没有清除creds…如果我在方法末尾放置断点并运行代码，它会工作，但如果没有断点，它就不工作，方法如下：

- (void)LogoutButtonPressed
{

    //@TODO: Fix Logout
    /*NSURLCredentialStorage *credentialStorage = [NSURLCredentialStorage sharedCredentialStorage];
    NSDictionary *credentialsDicationary = [credentialStorage allCredentials];


    for (NSURLProtectionSpace *space in [credentialsDicationary allKeys]) {

        NSDictionary *spaceDictionary = [credentialsDicationary objectForKey:space];

        for (id userName in [spaceDictionary allKeys]) {

            NSURLCredential *credential = [spaceDictionary objectForKey:userName];

            [credentialStorage removeCredential:credential forProtectionSpace:space];

        }

    }*/

    // reset the credentials cache...
    NSDictionary *credentialsDict = [[NSURLCredentialStorage sharedCredentialStorage] allCredentials];

    if ([credentialsDict count] > 0) {
        // the credentialsDict has NSURLProtectionSpace objs as keys and dicts of userName => NSURLCredential
        NSEnumerator *protectionSpaceEnumerator = [credentialsDict keyEnumerator];
        id urlProtectionSpace;

        // iterate over all NSURLProtectionSpaces
        while (urlProtectionSpace = [protectionSpaceEnumerator nextObject]) {
            NSEnumerator *userNameEnumerator = [[credentialsDict objectForKey:urlProtectionSpace] keyEnumerator];
            id userName;

            // iterate over all usernames for this protectionspace, which are the keys for the actual NSURLCredentials
            while (userName = [userNameEnumerator nextObject]) {
                NSURLCredential *cred = [[credentialsDict objectForKey:urlProtectionSpace] objectForKey:userName];
                NSLog(@"cred to be removed: %@", cred);
                [[NSURLCredentialStorage sharedCredentialStorage] removeCredential:cred forProtectionSpace:urlProtectionSpace];
            }
        }
    }


    [loginMenuView setFrame:CGRectMake(loginMenuView.frame.origin.x, loginMenuView.frame.origin.y, 410, 184)];
    [logingMetalBg setFrame:CGRectMake(loginMenuView.bounds.origin.x, loginMenuView.bounds.origin.y, loginMenuView.bounds.size.width, loginMenuView.bounds.size.height)];
    /*LHAppDelegate *appDelegate = (LHAppDelegate *)[[UIApplication sharedApplication] delegate];
    [appDelegate.loginSession setString:@""];
    [appDelegate.nameOfUser setString:@""];*/
    [logoutButton removeFromSuperview];
    logoutButton = nil;
    //[[logoutPopup getPopOver ]dismissPopoverAnimated:NO];
    //logoutPopup = nil;
    [settingsPage hide];
    [self.menu removeFromSuperview];
    self.menu = nil;
    menuItems = nil;
    [self MenuOrLogin];

}

我从这个例子中得到了以下代码：

我做错了什么

方法中的代码也会出现警告：

/Users/jsuske/Documents/SSiPad(Device Only)ios7/SchedulingiPadApplication/ViewControllers/LHLoginController.m:523:105: Local declaration of 'userName' hides instance variable

---

为什么会发生这种情况？

您会收到警告，因为您使用了一个本地属性

userName

，并且已经实现了一个同名的全局属性。重命名它们可以消除警告。