Python快速学习

（最近由于IDA Pro中需要使用脚本，而自带的IDC貌似不怎么好用，所以就学习了下Python的基本语法。）

一、经典程序Hello world

print "Hello world!"

raw_input("P...By betabin.");

二、中文编码使用

# -*- coding:GBK -*-
print "你好，中国"

raw_input("Press enter key to close this window...");

三、List数据结构

word="abcdefg"
a=word[2]
print "a is: "+a
b=word[1:3]
print "b is: "+b # index 1 and 2 elements of word.
c=word[:2]
print "c is: "+c # index 0 and 1 elements of word.
d=word[0:]
print "d is: "+d # All elements of word.
e=word[:2]+word[2:]
print "e is: "+e # All elements of word.
f=word[-1]
print "f is: "+f # The last elements of word.
g=word[-4:-2]
print "g is: "+g # index 3 and 4 elements of word.
h=word[-2:]
print "h is: "+h # The last two elements.
i=word[:-2]
print "i is: "+i # Everything except the last two characters
l=len(word)
print "Length of word is: "+ str(l)

四、条件语句

# Multi-way decision
x=int(raw_input("Please enter an integer:"))
if x<0:
    x=0
    print "Negative changed to zero"
elif x==0:
    print "Zero"
else:
    print "More"
    

五、循环语句

# Loops List
a = ['beta', 'bin', 'betabin']
for x in a:
    print x, len(x)

六、函数定义

# Define and invoke function.
def sum(a,b):
    return a+b

func = sum
r = func(5,6)
print r

# Defines function with default argument
def add(a,b=2):
    return a+b

r=add(1)
print r
r=add(1,5)
print r

七、文件I/O

spath="D:/WorkSpace/Python/t.txt"
f=open(spath,"w") # Opens file for writing.Creates this file doesn't exist.

f.write("First line 1.\n")
f.writelines("First line 2.")

f.close()

f=open(spath,"r") # Opens file for reading

for line in f:
    print line

f.close()

八、异常处理

s=raw_input("Input your age:")
if s =="":
    raise Exception("Input must no be empty.")

try:
    i=int(s)
except ValueError:
    print "Could not convert data to an integer."
except:
    print "Unknown exception!"
else: # It is useful for code that must be executed if the try clause does not raise an exception
    print "You are %d" % i," years old"
finally: # Clean up action
    print "Goodbye!"

九、类与继承

class Base:
    def __init__(self):
            self.data = []
            self.x = 23
    def add(self, x):
        self.data.append(x)
    def addtwice(self, x):
        self.add(x)
        self.add(x)

#Child extends Base
class Child(Base):
    def plus(self, a, b):
        return a + b + self.x

oChild = Child()
oChild.add("str1")

print oChild.data
print oChild.x
print oChild.plus(2, 3)

十、包

# apacket.py
def add_func(a, b):
    return a + b

# bpacket.py

from apacket import add_func # Also can be: import apacket

print "Import function:"
print add_func(1,2) # If using "import apacket", then here should be "apacket.add_func"

从上面的十个实例中，其实可以看出Python的基本语法规则。比如说变量弱类型，不需要先定义，类的继承类似public继承等。当然，Python不会这么简单，要学会还需要深入的了解，不过，暂时应付IDA Pro的脚本，这些知识应该足够了。不行的话，再谷歌吧。