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python检测文件的MD5值

2013-08-01 11:54 by 江湖么名, ... 阅读, ... 评论, 收藏, 编辑

python检测文件的MD5值
MD5(单向散列算法)的全称是Message-Digest Algorithm 5(信息-摘要算法),经MD2、MD3和MD4发展而来。MD5算法的使用不需要支付任何版权费用。

#python 检测文件MD5值
#python version 2.6
 
import hashlib
import os,sys
 
#简单的测试一个字符串的MD5值
def GetStrMd5(src):
    m0=hashlib.md5()
    m0.update(src)
    print m0.hexdigest()
    pass
 
#大文件的MD5值
def GetFileMd5(filename):
    if not os.path.isfile(filename):
        return
    myhash = hashlib.md5()
    f = file(filename,'rb')
    while True:
        b = f.read(8096)
        if not b :
            break
        myhash.update(b)
    f.close()
    return myhash.hexdigest()
 
def CalcSha1(filepath):
    with open(filepath,'rb') as f:
        sha1obj = hashlib.sha1()
        sha1obj.update(f.read())
        hash = sha1obj.hexdigest()
        print(hash)
        return hash
 
def CalcMD5(filepath):
    with open(filepath,'rb') as f:
        md5obj = hashlib.md5()
        md5obj.update(f.read())
        hash = md5obj.hexdigest()
        print(hash)
        return hash        
 
if __name__ == "__main__":
    if len(sys.argv)==2 :
        hashfile = sys.argv[1]
        if not os.path.exists(hashfile):
            hashfile = os.path.join(os.path.dirname(__file__),hashfile)
            if not os.path.exists(hashfile):
                print("cannot found file")
            else
                CalcMD5(hashfile)
        else:
            CalcMD5(hashfile)
            #raw_input("pause")
    else:
        print("no filename")