php pack导出数据倒excel表中文乱码问题

需要用php将数据导出倒excel表中，用的是php的pack函数将字符打包成二进制，然后写入Excel表格文件，英文字符导入正常，现在中文字符全部乱码了，不知道哪里设置的问题呢？

<?php
/**
 * Simple excel writer class with no external dependencies, drop it in and have fun
 * @author Matt Nowack
 * @link https://gist.github.com/ihumanable/929039/edit
 * @license Unlicensed
 * @version 1.0
 */
class Excel {
  private $col;
  private $row;
  private $data;
  private $title;
  
  /**
   * Safely encode a string for use as a filename
   * @param string $title The title to use for the file
   * @return string The file safe title
   */
  static function filename($title) {
    $result = strtolower(trim($title));
    $result = str_replace("'", '', $result);
    $result = preg_replace('#[^a-z0-9_]+#', '-', $result);
    $result = preg_replace('#\-{2,}#', '-', $result);
    return preg_replace('#(^\-+|\-+$)#D', '', $result);
  }
  
  /**
   * Builds a new Excel Spreadsheet object
   * @return Excel The Spreadsheet
   */
  function __construct($title) {
    $this->title = $title;
    $this->col = 0;
    $this->row = 0;
    $this->data = '';
    $this->bofMarker();
  }
  
  /**
   * Transmits the proper headers to cause a download to occur and to identify the file properly
   * @return nothing
   */
  function headers() {
    header("Content-Type: application/force-download");
    header("Content-Type: application/octet-stream");
    header("Content-Type: application/download");
    header("Content-Type: application/vnd.ms-excel; charset=iso-8859-1");
    header("Content-Disposition: attachment;filename=" . Excel::filename($this->title) . ".xls ");
    header("Content-Transfer-Encoding: binary ");
  }
  
  function send() {
    $this->eofMarker();
    // $this->headers();
    echo $this->data;
  }
  
  /**
   * Writes the Excel Beginning of File marker
   * @see pack()
   * @return nothing
   */
  private function bofMarker() { 
    $this->data .= pack("ssssss", 0x809, 0x8, 0x0, 0x10, 0x0, 0x0);  
  }
  
  /**
   * Writes the Excel End of File marker
   * @see pack()
   * @return nothing
   */
  private function eofMarker() { 
    $this->data .= pack("ss", 0x0A, 0x00); 
  }
  
  /**
   * Moves internal cursor left by the amount specified
   * @param optional integer $amount The amount to move left by, defaults to 1
   * @return integer The current column after the move
   */
  function left($amount = 1) {
    $this->col -= $amount;
    if($this->col < 0) {
      $this->col = 0;
    }
    return $this->col;
  }
  
  /**
   * Moves internal cursor right by the amount specified
   * @param optional integer $amount The amount to move right by, defaults to 1
   * @return integer The current column after the move
   */
  function right($amount = 1) {
    $this->col += $amount;
    return $this->col;
  }
  
  /**
   * Moves internal cursor up by amount
   * @param optional integer $amount The amount to move up by, defaults to 1
   * @return integer The current row after the move
   */  
  function up($amount = 1) {
    $this->row -= $amount;
    if($this->row < 0) {
      $this->row = 0;
    }
    return $this->row;
  }
  
  /**
   * Moves internal cursor down by amount
   * @param optional integer $amount The amount to move down by, defaults to 1
   * @return integer The current row after the move
   */
  function down($amount = 1) {
    $this->row += $amount;
    return $this->row;
  }
  
  /**
   * Moves internal cursor to the top of the page, row = 0
   * @return nothing
   */
  function top() {
    $this->row = 0;
  }
  
  /**
   * Moves internal cursor all the way left, col = 0
   * @return nothing
   */
  function home() {
    $this->col = 0;
  }
  
  /**
   * Writes a number to the Excel Spreadsheet
   * @see pack()
   * @param integer $value The value to write out
   * @return nothing
   */
  function number($value) { 
    $this->data .= pack("sssss", 0x203, 14, $this->row, $this->col, 0x0); 
    $this->data .= pack("d", $value); 
  }
  
  /**
   * Writes a string (or label) to the Excel Spreadsheet
   * @see pack()
   * @param string $value The value to write out
   * @return nothing
   */
  function label($value) { 
    $length = strlen($value);
    // ob_iconv_handler()
    // $value = iconv('UTF-8','gbk',$value);
    // file_put_contents('a.txt', 'test:    '.)
    $this->data .= pack("ssssss", 0x204, 8 + $length, $this->row, $this->col, 0x0, $length); 
    $this->data .= $value; 
  }
}

下面是我的调用测试代码：

<?php 
    // iconv_set_encoding('output_encoding','gbk');
    require_once("excel.php");

    $xls = new Excel('Report');

    $colors = array(
        array("red", "blue", "green", "yellow", "orange", "purple"),
        array('过以上','以','c','过','目录','f')
    );

    foreach ($colors as $key => $value) {
        $xls->home();
        foreach ($value as  $row) {
          // $xls->home();
          $xls->label($row);
          $xls->right();
           // $xls->label($row);
        }
        $xls->down();
    }
    
    ob_start();
    $xls->send();
    $data = ob_get_clean();
    file_put_contents(__DIR__ .'/report.xls', $data);

---

你中文是什么编码的啊？Excel默认是GB2312的。如果UTF-8就乱码了。

解决办法：要么转成GB2312再写进去。
要么在最后先输出BOM头

    ob_start();
    $xls->send();
    $data = "\xEF\xBB\xBF" . ob_get_clean();
    file_put_contents(__DIR__ .'/report.xls', $data);