python实用代码

lxy777

　　1. python下载（http）文件并保存
　　import urllib2
request = urllib2.Request("http://www.appchina.com/market/r/639017/com.sohu.inputmethod.sogou.apk?channel=aplus.direct&p=aplus.index&uid=gAJ9cQFVC3ZlcmlmeV9jb2RlcQJVBGt1dWxxA3Mu1UNbT0ifMPYMADcmCTSaFDqhBcjWwME7w&page=appplus.category&ref=appplus.main")
　　response = urllib2.urlopen(request)
　　#test
file_size = int(response.headers['content-length'])
print file_zise
　　#test
　　with open("E:\\tmp\\tmp.apk", 'wb') as output:
    while True:
        buffer = response.read(1024*256)
        if not buffer:
            break
        output.write(buffer)
　　或者
　　import urllib
import os

def reporthook(blocks_read, block_size, total_size):
    """total_size is reported in bytes.
    block_size is the amount read each time.
    blocks_read is the number of blocks successfully read.
    """
    if not blocks_read:
        print 'Connection opened'
        return

    if total_size < 0:
        # Unknown size
        print 'Read %d blocks (%d bytes)' % (blocks_read,
                                             blocks_read * block_size)

    else:
        amount_read = blocks_read * block_size
        print 'Read %d blocks, or %d/%d' % \
            (blocks_read, amount_read, total_size)
    return

try:
    filename, msg = urllib.urlretrieve(
        'http://blog.doughellmann.com/',
        reporthook=reporthook)
    print
    print 'File:', filename
    print 'Headers:'
    print msg
    print 'File exists before cleanup:', os.path.exists(filename)

finally:
    urllib.urlcleanup()

    print 'File still exists:', os.path.exists(filename)


　　2. 线程示例
　　import thread,time

count = 0
lock = thread.allocate_lock()

def threadTest():
    global count, lock
    #lock.acquire()
    for i in range(10000):
        count += 1
    #lock.release()
for i in range(10):
    thread.start_new_thread(threadTest, ())
time.sleep(3)
print count;
　　3. threading的线程示例
　　import threading,time,random

count = 0;

class ThreadClass(threading.Thread):
    def __init__(self, lock, threadName):
        threading.Thread.__init__(self, name = threadName)
        self.lock = lock
        print threadName

    def run(self):
        global count
        self.lock.acquire()
        for i in range(10000):
            count += 1
        print count
        self.lock.release()
       
lock = threading.Lock()
for i in range(10):
    ThreadClass(lock, "thread-" + str(i)).start()
time.sleep(3)
print count
　　4. 队列应用
　　import threading,Queue,time

queue = Queue.Queue(0)
SIZE = 15

class ThreadClass(threading.Thread):
    def __init__(self, job, type):
        super(ThreadClass, self).__init__()
        self.job = job
        self.type = type

    def run(self):
        while True:
            if self.job.qsize() > 0:
                data = self.job.get()
                taskfun(data, self.type)
            else:
                print
                print "thread-%s no job \n" %str(self.type)
                print
                break

def taskfun(data, type):
    time.sleep(1)
    print "data=%s,type=%s" %(str(data), str(type))

for j in range(3):
    queue.put(j)

print "queue size:%s" %str(queue.qsize())
for i in range(10):
    ThreadClass(queue, i).start()
time.sleep(5)