Question

<form action="send_post.php" method="post">  
   <p>A: <input type="text" name="A">  
   <p>B: <input type="text" name="B">                                       
   <p><input type="submit">    
</form>     
<?php    
    $db = "localhost"; $usr = "blah1"; $pword = "blah2"; $dbname = "blah3"; 
    -----connects to server ok -------            
    $A = mysqli_real_escape_string($conn, $_POST['A']);  
    $B = mysqli_real_escape_string($conn, $_POST['B']);   
    $query="SELECT * FROM blah4 where A=$A and B=$B";     
    $sql=mysqli_query($conn, $query);         
    echo $sql;                                                
    $conn->clos();                                                                 
?>

从数据库显示数据需要什么？

Answer 1

您的查询字符串格式不正确

<form action="send_post.php" method="post">  
   <p>A: <input type="text" name="A"> </p> 
   <p>B: <input type="text" name="B"> </p>                                     
   <p><input type="submit">    </p>
</form>     
<?php    
    $db = "localhost"; $usr = "blah1"; $pword = "blah2"; $dbname = "blah3"; 
    -----connects to server ok -------            
    $A = mysqli_real_escape_string($conn, $_POST['A']);  
    $B = mysqli_real_escape_string($conn, $_POST['B']);   
    $query="SELECT * FROM blah4 where A='$A' and B='$B'";     
    $sql=mysqli_query($conn, $query);         
    echo $sql;                                                
    $conn->close();                                                                 
?>

或

  $query="SELECT * FROM blah4 where A='".  $A ,"' and B='" .$B ."'";

您还没有关闭</p>

和

$conn->close();

Answer 2

要添加不实际从db获取数据，请尝试此

$row->mysqli_result::fetch_object($query);

那么你可以得到某些字段，比如你有一个用户名字段

username = $row->username;

然后你可以显示像

这样的用户名

echo $username;

无法获取显示的查询结果 - php / mysqli

2 个答案: