Question

我正在开发一个网络浏览器应用程序，但目前我遇到了错误：“预期的标识符或'（'”并且我不知道该怎么做。以下是显示错误的代码：

{:here is the error
    NSURL *url = [NSURL URLWithString:urlString];
    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
    [self.webView loadRequest:urlRequest];
}

非常感谢帮助。

更新：

我不知道我应该给你的其他代码，所以这里是ViewController.m文件中的整个代码：

#import "ViewController.h"

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIWebView *webView;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *back;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *refresh;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *stop;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *forward;

- (void)loadRequestFromString:(NSString*)urlString;

{ *HERE IS THE ERROR:EXPECTED IDENTIFIER OR '('*
    NSURL *url = [NSURL URLWithString:urlString];
    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
    [self.webView loadRequest:urlRequest];
}

@end

@implementation ViewController ***HERE IS A WARNING SAYING:METHOD DEFINITION FOR 'LOADREQUESTFROMSTRING:'NOT FOUND***

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any `enter code here`additional setup after loading the view, typically from a nib.
    [self loadRequestFromString:@"http://www.apple.com/startpage/"];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

Answer 1

为什么在界面中有实现代码

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIWebView *webView;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *back;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *refresh;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *stop;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *forward;

// This is a private interface and doesn't need the below line ever.
// If you want this public then add it to the interface in the .h file.
- (void)loadRequestFromString:(NSString*)urlString;

*****************************************************************************
// This is implementation code and shouldn't be here. 
// This belongs in the implementation not the interface
{ *HERE IS THE ERROR:EXPECTED IDENTIFIER OR '('*
    NSURL *url = [NSURL URLWithString:urlString];
    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
    [self.webView loadRequest:urlRequest];
}
*****************************************************************************
@end

在您的实施中@implementation添加

@implementation ViewController
// Your other code such as viewDidLoad etc

// Adding this method to the implementation will also get rid of the warning
// ***HERE IS A WARNING SAYING:METHOD DEFINITION FOR 'LOADREQUESTFROMSTRING:'NOT FOUND***
// As it will now be implemented but there is no reason to declare the method in a private interface
- (void)loadRequestFromString:(NSString*)urlString;
{ 
    NSURL *url = [NSURL URLWithString:urlString];
    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
    [self.webView loadRequest:urlRequest];
}

由于这是实现代码，因此它不应存在于接口中。

预期标识符或（

1 个答案: