Php 如何在变量参数函数中使用查询?

Php 如何在变量参数函数中使用查询?,php,mysql,Php,Mysql,带有变量参数的查询只接受第一个参数 我尝试从foreach循环ant回显所有变量参数,但当我键入query时,它只在第一个参数上完成 function SelectDB($Table,$Stm,$Value,...$Selectors){ global $conn; foreach($Selectors as $Selector){ //That works and echo all Selectors echo $Selector; } } function SelectDB(

带有变量参数的查询只接受第一个参数

我尝试从foreach循环ant回显所有变量参数,但当我键入query时,它只在第一个参数上完成

function SelectDB($Table,$Stm,$Value,...$Selectors){
global $conn;
foreach($Selectors as $Selector){
  //That works and echo all Selectors
  echo $Selector; 
 } 
 }
function SelectDB($Table,$Stm,$Value,...$Selectors){
  global $conn;
   foreach($Selectors as $Selector){
  //Only First Selector is executed in Query
  $Query = $conn->prepare("SELECT $Selector FROM $Table WHERE $Stm = ?");
  $Query->execute(array($Value)); 
  $Fetch = $Query->fetch();
  return $Fetch;
   } 
 }
$S = SelectDB("attended","Id",1,"Id","s","Date","TeacherId");
echo $S['TeacherId']; //Undefined Index
echo $S['Id']; //echo The Id 

我想对循环中使用的
return
语句中的每个选择器执行查询,因此它将在第一次迭代时返回

使用缓冲区存储数据并返回:

function SelectDB($Table,$Stm,$Value,...$Selectors) {
  global $conn;
  $result = [];
  foreach($Selectors as $Selector) {
    //Only First Selector is executed in Query
    $Query = $conn->prepare("SELECT $Selector FROM $Table WHERE $Stm = ?");
    $Query->execute(array($Value)); 

    // push fetch to result
    $result []= $Query->fetch();
 }

 return $result;
}

因为你们不明白return是做什么的。我尝试回显获取数据,它成功了,但当我将它们存储在数组中并返回数组时,它给出了相同的索引错误