diff --git a/extend/base/FileUtil.php b/extend/base/FileUtil.php
index da5c5a696..111ffa205 100755
--- a/extend/base/FileUtil.php
+++ b/extend/base/FileUtil.php
@@ -332,8 +332,11 @@ class FileUtil
             Header("Content-Disposition: attachment; filename=".$show_name);
 
             // 清除前面输出的内容
-            ob_clean();
-            flush();
+            if(ob_get_length() > 0)
+            {
+                ob_clean();
+                flush();
+            }
 
             //一次性将数据传输给客户端
             //echo fread($file, filesize($file_path));
diff --git a/extend/base/Qrcode.php b/extend/base/Qrcode.php
index 05ad420a3..646416a31 100644
--- a/extend/base/Qrcode.php
+++ b/extend/base/Qrcode.php
@@ -61,7 +61,10 @@ class Qrcode
         $content = isset($params['content']) ? base64_decode(urldecode(trim($params['content']))) : __MY_URL__;
 
         // 生成二维码并输出页面显示
-        ob_clean();
+        if(ob_get_length() > 0)
+        {
+            ob_clean();
+        }
         \QRcode::png($content, false, $level, $point_size, $mr);
     }
 
diff --git a/extend/base/Verify.php b/extend/base/Verify.php
index 559aee8af..38664fef6 100755
--- a/extend/base/Verify.php
+++ b/extend/base/Verify.php
@@ -125,7 +125,10 @@ class Verify
 		$this->KindofSession();
 
 		// 输出图像
-		ob_clean();
+		if(ob_get_length() > 0)
+        {
+            ob_clean();
+        }
 		header('Content-Type: image/gif');
 		imagegif($this->img);