Question

正则表达式在某些情况下只能工作，而在其他情况下则不能工作。

我希望正则表达式仅匹配两个“ {} {}”的组，而{}之间没有任何匹配

Answer 1

我猜我们只想使用类似于以下的表达式捕获演示中列出的三个输入：

 public function login(Request $request)
{
    $validatedData = $request->validate([
        'email' => 'required',
        'password' => 'required'
    ]);
    $email = $request->email;
    $password = $request->password;
    //If the user checked the remember me checkbox then make sure to remember him
    if(isset($request->rememberMe)) {
        if (\Auth::attempt(['email' => $email, 'password' => $password], true)) {
            $user = User::findOrFail($email);
            //Remember the user
            \Auth::login($user, true);
            return redirect('/home');
        } else {
            //Otherwise redirect back to login page with errors.
            return redirect()->back()->withInput()->withErrors('Invalid email  or password');
        }
        //If the user didn't check the remember me checkbox then don't remember him.
    } else {
        if (\Auth::attempt(['email' => $email, 'password' => $password])) {
            $user = User::findOrFail($email);
            \Auth::login($user);
            return redirect('/home');
        } else {
            //Otherwise redirect back to login page with errors.
            return redirect()->back()->withInput()->withErrors('Invalid email or password');
        }
    }
}

Demo 1

或

(\{.*?\}(.+?){.*?\})

Demo 2

Answer 2

模式第一部分中的.*?正在遍历输入的意外部分，直到找到为止，因为.接受了所有这些字符。仅用?来使量词变得懒惰是不够的-它会继续进行直到找到匹配项。

\{[^}]*?\}\s\{[^}]*?\}

https://regex101.com/r/p5u3N6/5

Answer 3

不确定我是否理解您的要求，我想您只希望成对的{}{}匹配，并且在这两个之间只允许一个空格。您可以尝试使用此\{([^\{]+)\}\ \{([^\}]+)\}。

正则表达式始终无法正常工作，为什么？

3 个答案:

Demo 1

Demo 2