無法訪問heredoc中的數組

Question

爲什麼此代碼在我嘗試訪問的行上發出錯誤$sector_value['sector_info']['purchase_order'];？但不是在我打印出變量$sector_counter的第五行？

//SECTOR 
$email_body .= <<<SECTOR_DETAILS 
    <tr> 
     <td colspan="2"> 
      Sector $sector_counter; 
     </td> 
    </tr> 

    <tr> 
     <td colspan="2"> 
      Purchase order 
     </td> 
    </tr> 
    <tr> 
     <td colspan="2"> 
     $sector_value['sector_info']['purchase_order']; 
     </td> 
    </tr> 

    <tr> 
     <td> 
      Proof 
     </td> 
    </tr> 

SECTOR_DETAILS; 

這是錯誤：

Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING in /home/www2isco/public_html/test/bch/queries/submit_order.php on line 44

謝謝！

Answer 1

將變量括在{ .. }中，它在the docs中。

//SECTOR 
$email_body .= <<<SECTOR_DETAILS 
    <tr> 
     <td colspan="2"> 
      Sector $sector_counter; 
     </td> 
    </tr> 

    <tr> 
     <td colspan="2"> 
      Purchase order 
     </td> 
    </tr> 
    <tr> 
     <td colspan="2"> 
     {$sector_value['sector_info']['purchase_order']} 
     </td> 
    </tr> 

    <tr> 
     <td> 
      Proof 
     </td> 
    </tr> 

SECTOR_DETAILS;