擅长:python、mysql、java
<p>写入文件后,必须倒带(查找)
在阅读之前,把它放回到开头</p>
<p>在print语句之前添加以下行</p>
<pre><code>openfile.seek(0)
</code></pre>
<p>seek及其参数的文档
<a href="https://docs.python.org/3/library/io.html?highlight=seek#io.IOBase.seek" rel="nofollow noreferrer">https://docs.python.org/3/library/io.html?highlight=seek#io.IOBase.seek</a></p>
<p>请注意,如果要从同一进程(有线程或无线程)中读取新写入的文件,seek是最好、最有效的方法</p>
<p><strong>附录:(进程间场景)</strong>
但是,如果要从另一个进程读取该文件,则必须刷新该文件或将其关闭。(如果您想继续在流程中读写,则首选刷新方式</p>
<p>假设您有两个脚本:</p>
<p>脚本1.py</p>
<pre><code> openfile = open(filename, 'a+')
openfile.write(newData)
# without next line, data might not be readable
# by another process
openfile.flush()
tell_script2_it_can_read_the_file()
return
</code></pre>
<p>脚本2.py</p>
<pre><code>wait_for_notification_from_script1()
with open(filename) as openfile:
print(openfile.read())
</code></pre>