python的传参测试

结论：传参如果是list map 将会修改其值。这意味着list map 是引用传递的。

而 int string 为值传递。

 

#!/usr/bin/dev python

import sys
import os

def FixInt(nVal):
    nVal = nVal + 1;
    
def FixString(strVal):
    strVal = strVal + '_b';    

def FixMap(map):
    for key in map:
        map[key] = map[key] + '_b'; 

def FixList(ls):
    ls.append('1');
    
def PrintVal(strInfo, nVal, strVal, map, ls):
    if strInfo:
        print("==== %s =====" %strInfo);
        
    print("int value:%d" %nVal);
    print("string value:%s" %strVal);
    print("map value:%s" %map);
    print("list value:%s" %ls);
    print("\n\n");    

if "__main__" == __name__:
    nTmp = 0;
    strTmp = "aaaa";
    
    mapTmp = {
        "aaa" : "111",
        "bbb" : "222",
        "ccc" : "333",
        "ddd" : "444"
    }
    
    lsTmp = ['a', 'b', 'c']

    
    PrintVal("The orgin value", nTmp, strTmp, mapTmp, lsTmp);    

    FixInt(nTmp);
    FixString(strTmp);
    FixMap(mapTmp);
    FixList(lsTmp);
    
    PrintVal("The dst value", nTmp, strTmp, mapTmp, lsTmp);
    
    

    

 结果：

==== The orgin value =====
int value:0
string value:aaaa
map value:{'aaa': '111', 'bbb': '222', 'ccc': '333', 'ddd': '444'}
list value:['a', 'b', 'c']



==== The dst value =====
int value:0
string value:aaaa
map value:{'aaa': '111_b', 'bbb': '222_b', 'ccc': '333_b', 'ddd': '444_b'}
list value:['a', 'b', 'c', '1']