Question

我想从数据库中获取数据，并希望存储到数组中，并在将数据存储到数组后，我想访问数组的特定索引。我是一个java开发人员需要在php中做这个（我不太了解）。基本上，表中有250个字符串，我想将这250个字符串读入和数组，并希望访问某个特定的行。例如：

 <?php 
 $con=mysqli_connect("example.com","peter","abc123","my_db");
 // Check connection
 if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$result = mysqli_query($con,"SELECT * FROM Persons");

echo "<table border='1'>
<tr>
<th>Firstname</th>
<th>Lastname</th>
</tr>";

while($row = mysqli_fetch_array($result)) {
  echo "<tr>";
  echo "<td>" . $row['FirstName'] . "</td>";
  echo "<td>" . $row['LastName'] . "</td>";
  echo "</tr>";
}

echo "</table>";

**$uname100 = $row[100]; // this is not getting assigned to $uname100 variable**
**echo $row[100]; // here this is not printing** 
**echo $uname100; // not even this printing**
mysqli_close($con); 
?>

请检查代码中的粗体部分并帮助我。我是php的新手，所以请不要对此感到恐慌。

还想做这样的事情：

$ctr=0;
while($row = mysqli_fetch_array($result)) {
  echo "<tr>";
  echo "<td>" . $row['FirstName'] . "</td>";
  echo "<td>" . $row['LastName'] . "</td>";
  echo "</tr>";
$uname[$ctr++] = $row['FirstName']; // AND USING THIS OUTSIDE LOOP
}

echo $uname[90];

Answer 1

使用数组构造

$counter=0;
$data = array();

while($row = mysqli_fetch_array($result)) {
   echo "<tr>";
   echo "<td>" . $row['FirstName'] . "</td>";
   echo "<td>" . $row['LastName'] . "</td>";
   echo "</tr>";
   $data[] = $row['FirstName'];
   $counter++;
}
print_r($data);

Answer 2

您无法访问while循环外的变量$ row [100]。 $ row也不包含索引100。在while循环中它只包含$ row ['FirstName']或$ row ['LastName']

第二部分答案：

$uname = array();
$ctr=0;
while($row = mysqli_fetch_array($result)) {
  ....
  ....

  $uname[$ctr++] = $row['FirstName']; // AND USING THIS OUTSIDE LOOP
}

if(isset($uname[90])) echo $uname[90];

Answer 3

第一个解决方案

$counter=0;
while($row = mysqli_fetch_array($result)) {

echo "<tr>";
echo "<td>" . $row['FirstName'] . "</td>";
echo "<td>" . $row['LastName'] . "</td>";
echo "</tr>";
$counter++;
$varName='uname'.$counter;
$$varName=$row['FirstName'];
}

echo echo $uname100;

PHP：获取数据并存储到变量中

3 个答案: