1. 最简单下载:将文件流放入HttpResponse对象即可，适合小文件的下载，但如果这个文件非常大，这种方式会占用大量. 如：
def file_download(request):
# do something...
with open('file_name.txt') as f:
c = f.read()
return HttpResponse(c)
2. 合理的文件下载
Django的HttpResponse对象允许将迭代器作为传入参数，将上面代码中的传入参数c换成一个迭代器 ，便可以将上述下载功能优化为对大小文件均适合.更加合理的文件下载功能，应该先写一个迭代器，用于处理文件， 然后将这个迭代器作为参数传递给StreaminghttpResponse对象，如：
from django.http import StreamingHttpResponse def big_file_download(request):
# do something... def file_iterator(file_name, chunk_size=):
with open(file_name) as f:
while True:
c = f.read(chunk_size)
if c:
yield c
else:
break the_file_name = "file_name.txt"
response = StreamingHttpResponse(file_iterator(the_file_name)) return response
3.最优文件下载
上述的代码，已经完成了将服务器上的文件，通过文件流传输到浏览器，但文件流通常会以乱码形式显示到浏览器中， 而非下载到硬盘上，因此，还要在做点优化，让文件流写入硬盘。优化很简单，给StreamingHttpResponse对象 的Content-Type和Content-Disposition字段赋下面的值即可，如：
response['Content-Type'] = 'application/octet-stream'
response['Content-Disposition'] = 'attachment;filename="test.pdf"' 完整代码如下: from django.http import StreamingHttpResponse def big_file_download(request):
# do something... def file_iterator(file_name, chunk_size=):
with open(file_name) as f:
while True:
c = f.read(chunk_size)
if c:
yield c
else:
break the_file_name = "big_file.pdf"
response = StreamingHttpResponse(file_iterator(the_file_name))
response['Content-Type'] = 'application/octet-stream'
response['Content-Disposition'] = 'attachment;filename="{0}"'.format(the_file_name) return response
4.文件名包含中文下载时文件名不对,原因是: url编码解码 ,解决方法如下
from django.utils.http import urlquote response[‘Content-Disposition‘] = ‘attachment;filename="%s"‘ % (urlquote(title))
5. 遇到的问题：
下面可以下载成功：
def cmdb_export(request):
"""
下载文件，发调用写好的 下载文件的 函数总是报错，直接写过来没问题.
:param request:
:return:
"""
if request.method=="GET":
print("导出ip...........hosts")
dir_create()
remove_file("hosts")
obj = ServerConfInfo.objects.filter(deleted=False)
for i in obj:
filename = file_creat(file_name='hosts', mode="a", content=i.ip_net) response = StreamingHttpResponse(file_iterator(filename))
response['Content-Type'] = 'application/octet-stream'
response['Content-Disposition'] = 'attachment;filename="{0}"'.format(filename)
return response else:
pass
可是改成调用写好的下载函数就报错 didn't return an HttpResponse object. It returned None instead
def cmdb_export(request):
"""
下载文件，发调用写好的 下载文件的 函数总是报错，直接写过来没问题.
:param request:
:return:
"""
if request.method=="GET":
print("导出ip...........hosts")
dir_create()
remove_file("hosts")
obj = ServerConfInfo.objects.filter(deleted=False)
for i in obj:
filename = file_creat(file_name='hosts', mode="a", content=i.ip_net) dj_downloadfile(request,filename) ##这里调用写好的下载函数。
# txt = file_iterator(filename)
# response = StreamingHttpResponse(file_iterator(filename))
# response['Content-Type'] = 'application/octet-stream'
# response['Content-Disposition'] = 'attachment;filename="{0}"'.format(filename)
# return response else:
pass
dj_downloadfile（）函数如下：
def dj_downloadfile(request,filename):
"""
网页下载数据,发现引用该函数会出现错误，但是把代码拷贝过去是正常的.
:param request:
:param filename:
:return:
"""
response = StreamingHttpResponse(file_iterator(filename))
response['Content-Type'] = 'application/octet-stream'
response['Content-Disposition'] = 'attachment;filename="{0}"'.format(filename)
return response