如果不滿足單個條件，我該如何停止運行此代碼PHP

Question

即使條件未滿足，此代碼仍會運行到最後並提交。我想阻止它運行，並在錯過任何條件時回顯錯誤。請幫助。注意：我已經嘗試過exit（），它影響了運行時的整個html。

$verifiedPhone = phoneNumberValidator($phone); 
    $correctsurname = nameValidator($surname); 
    $correctlastname = nameValidator($lastname); 
    $correctusername = nameValidator($username); 
     if(!$verifiedPhone){ 
      echo "<p class='alert alert-warning'>Please use a Valid Phone Number</p>"; 

          } 
     if(!$correctsurname){ 
      echo "<p class='alert alert-warning'>Surname can only contain alphabets</p>"; 
          } 
     if(!$correctlastname) { 
      echo "<p class='alert alert-warning'>Last Name can only contain alphabets</p>"; 
          } 
     if (!$correctusername) { 
      echo "<p class='alert alert-warning'>Username can only contain alphabets</p>"; 
          } 
     $checkuser = " SELECT * FROM staff 
         WHERE username = '$correctusername'"; 
     $checkuserresult = mysqli_query($connection, $checkuser); 
     $checkuserrow = mysqli_num_rows($checkuserresult); 
    if($checkuserrow > 0){ 
     echo "<p class='alert alert-danger'>Username \"".$username."\" already exist! Try another</p>"; 
          } 
    else{ 
     $harsedpassword = md5("$password"); 
    $datainsert = " INSERT INTO staff (surname, lastname, phone, username, password) VALUES ('$correctsurname', '$correctlastname', '$verifiedPhone', '$username','$harsedpassword')"; 
$datainsertresult = mysqli_query($connection, $datainsert); 
    if($datainsertresult){ 
    echo "<p class='alert alert-success'><b>Staff Added Successfully</b></p>"; 
           } 

Answer 1

要麼使用別的IFS

if(!$correctsurname){ 
         echo "<p class='alert alert-warning'>Surname can only contain alphabets</p>"; 
} 
else if(!$correctlastname) { 
         echo "<p class='alert alert-warning'>Last Name can only contain alphabets</p>"; 
} 
else if (!$correctusername) { 
         echo "<p class='alert alert-warning'>Username can only contain alphabets</p>"; 
} 
else { 
    //the rest 

或死亡（ 「信息」），如果你必須：

if(!$correctsurname){ 
         die("<p class='alert alert-warning'>Surname can only contain alphabets</p>");  

}