回显包含“A”的数组字符串的 if 语句是什么 - What will be the if statement to echo the strings of the array containing 'A'?

What will be the if statement to echo the strings of the array containing 'A'?

if语句将回显包含"A"的数组的字符串？

法典：

<?php
$students=array(
array('roll_no'=>1,'name'=>'Sagar','percentage'=>78,'grade'=>'A'),
array('roll_no'=>2,'name'=>'Rahul','percentage'=>50,'grade'=>'C'),
array('roll_no'=>3,'name'=>'Emir','percentage'=>60,'grade'=>'B'),
);
foreach($students as $array)
{
foreach($array as $value)
{
    if($value['grade']='A')
    {
echo $value;
    }
}
}
?>

输出：

Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
Aagar
Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
A
Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
Aahul
Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
A
Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
Amir
Warning: Cannot use a scalar value as an array in C:'xampp'htdocs'php'Assignment41C.php on line 11
Warning: Illegal string offset 'grade' in C:'xampp'htdocs'php'Assignment41C.php on line 11
A

你不需要第二个foreach .每个$array值存储所有key => value对。所以你只需要检查grade键的值：

foreach ($students as $array) { 
     // note a double `==` which is a comparison operator
     if ($array['grade'] == 'A') {    
         // print_r instead of `echo` cause `echo` won't output array properly
         print_r($array);             
     }
}

看起来你在这里使用了额外的循环。此外，您可能需要重新检查此$value['grade']='A'部分。在 if 条件中，单个 = 表示赋值操作。使用 == 或 ===。

尝试此操作以仅打印成绩：

   foreach ($students as $array) {
     if($array['grade']== 'A') {
         echo $array['grade'];   // To show the grade only
      }
   }

尝试打印所有字段：

foreach($students as $array){
    if($array['grade']== 'A'){
        foreach($array as $k => $v) {
            echo "$k : $v";
            echo "<br/>";
        }
    }
}

希望这有帮助。

和平！ xD