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<p>我正在使用PyQt库拍摄网页截图,然后读取不同URL的CSV文件。我保留了一个变量提要,它在每次处理URL时都会递增,因此应该递增到URL的数量</p>
<p>以下是代码:</p>
<pre><code>webpage = QWebPage()
fo = open("C:/Users/Romi/Desktop/result1.txt", "w")
feed = 0
def onLoadFinished(result):
#fo.write( column1[feed])#, column2[feed], urls[feed])
#feed = 0
if not result:
print "Request failed"
fo.write(column1[feed])
fo.write(',')
fo.write(column2[feed])
fo.write(',')
#fo.write(urls[feed])
fo.write(',')
fo.write('404,image not created\n')
feed = feed + 1
sys.exit(1)
save_page(webpage, outputs.pop(0)) # pop output name from list and save
if urls:
url = urls.pop(0) # pop next url to fetch from list
webpage.mainFrame().load(QUrl(url))
fo.write(column1[feed])#,column2[feed],urls[feed],'200','image created','/n')
fo.write(',')
fo.write(column2[feed])
fo.write(',')
#fo.write(urls[feed])
fo.write(',')
fo.write('200,image created\n')
feed = feed + 1
else:
app.quit() # exit after last url
webpage.connect(webpage, SIGNAL("loadFinished(bool)"), onLoadFinished)
webpage.mainFrame().load(QUrl(urls.pop(0)))
#fo.close()
sys.exit(app.exec_())
</code></pre>
<p>它给了我一个错误:</p>
<pre><code>local variable feed referenced before the assignment at fo.write(column1[feed])#,column2[feed],urls[feed],'200','image created','/n')
</code></pre>
<p>知道为什么吗</p>