diff --git a/DrissionPage/_elements/chromium_element.py b/DrissionPage/_elements/chromium_element.py
index 8a20a44..ca373e1 100644
--- a/DrissionPage/_elements/chromium_element.py
+++ b/DrissionPage/_elements/chromium_element.py
@@ -517,10 +517,10 @@ class ChromiumElement(DrissionElement):
         if not result:
             return None
 
-        if is_blob:
+        elif is_blob:
             return result
 
-        if result['base64Encoded'] and base64_to_bytes:
+        elif result['base64Encoded'] and base64_to_bytes:
             from base64 import b64decode
             return b64decode(result['content'])
         else:
diff --git a/DrissionPage/_functions/web.py b/DrissionPage/_functions/web.py
index f3a458e..f731162 100644
--- a/DrissionPage/_functions/web.py
+++ b/DrissionPage/_functions/web.py
@@ -332,7 +332,7 @@ def is_cookie_in_driver(page, cookie):
 
 def get_blob(page, url, base64_to_bytes=True):
     if not url.startswith('blob'):
-        return None
+        raise TypeError('该链接非blob类型。')
     js = """
        function fetchData(url) {
       return new Promise((resolve, reject) => {
@@ -351,7 +351,7 @@ def get_blob(page, url, base64_to_bytes=True):
     try:
         result = page.run_js(js, url)
     except:
-        return None
+        raise RuntimeError('无法获取该资源。')
     if base64_to_bytes:
         from base64 import b64decode
         return b64decode(result.split(',', 1)[-1])
diff --git a/DrissionPage/items.py b/DrissionPage/items.py
index fea5bb6..0715e91 100644
--- a/DrissionPage/items.py
+++ b/DrissionPage/items.py
@@ -1,4 +1,10 @@
 # -*- coding:utf-8 -*-
+"""
+@Author   : g1879
+@Contact  : g1879@qq.com
+@Copyright: (c) 2024 by g1879, Inc. All Rights Reserved.
+@License  : BSD 3-Clause.
+"""
 from ._elements.chromium_element import ChromiumElement, ShadowRoot
 from ._elements.none_element import NoneElement
 from ._elements.session_element import SessionElement