python read文件内容的iter方式

遍历file的方式

复制代码iter(lambda: f.read(4096), "")等价与while True: data = f.read(4096) if not data: break hash_md5.updata(data)

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iter(lambda: f.read(4096), "")
等价与
while True:
    data = f.read(4096)
    if not data:
        break
    hash_md5.updata(data)

复制代码# 生成md5 def get_file_md5(fname): hash_md5 = hashlib.md5() with open(fname, "rb") as f: print type(f) for chunk in iter(lambda: f.read(4096), ""): hash_md5.update(chunk) return base64.b64encode(hash_md5.digest())

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# 生成md5
def get_file_md5(fname):
    hash_md5 = hashlib.md5()
    with open(fname, "rb") as f:
        print type(f)
        for chunk in iter(lambda: f.read(4096), ""):
            hash_md5.update(chunk)

    return base64.b64encode(hash_md5.digest())