正则表达式中的search、findall、finditer 区别

方法/属性	作用
match()	决定 RE 是否在字符串刚开始的位置匹配
search()	扫描字符串，找到这个 RE 匹配的位置
findall()	找到 RE 匹配的所有子串，并把它们作为一个列表返回
finditer()	找到 RE 匹配的所有子串，并把它们作为一个迭代器返回

import sys;
import re;
if __name__ == '__main__':
    strVal = '''<a href="http://www.andylin02.com" target="_blank" class="dsdfv">aaaa</a>
<a href="http://www.congfeng.com" target="_blank" class="tdsfv">bbbbsdf</a>
<a href="http://www.st.com" target="_blank" class="txx">ccccccc</a>
<a href="http://www.qs.com" target="_blank" class="xxx">ddddd</a>    
    ''';

    print(strVal);

    strPattern = r"(<\s*a\s.*href\s*=.*)"; 

    #search    
    mtReSearch = re.search(strPattern, strVal);

    print("======================= search result =======================");
    print("%s ==> %d" %(mtReSearch.groups(), len(mtReSearch.groups()) ));

    #findall
    lsFind = re.findall(strPattern, strVal);
    print("\n===================== findall result ========================");
    print("%s ==> %d" %(lsFind, len(lsFind)));

    #finditer
    print("\n===================== finditer result =======================")
    for mtFind in re.finditer(strPattern, strVal):
        print(mtFind.groups());
        print("------");

结果：

>>> 
<a href="http://www.andylin02.com" target="_blank" class="dsdfv">aaaa</a>
<a href="http://www.congfeng.com" target="_blank" class="tdsfv">bbbbsdf</a>
<a href="http://www.st.com" target="_blank" class="txx">ccccccc</a>
<a href="http://www.qs.com" target="_blank" class="xxx">ddddd</a>    

======================= search result =======================
('<a href="http://www.andylin02.com" target="_blank" class="dsdfv">aaaa</a>',) ==> 1

===================== findall result ========================
['<a href="http://www.andylin02.com" target="_blank" class="dsdfv">aaaa</a>', '<a href="http://www.congfeng.com" target="_blank" class="tdsfv">bbbbsdf</a>', '<a href="http://www.st.com" target="_blank" class="txx">ccccccc</a>', '<a href="http://www.qs.com" target="_blank" class="xxx">ddddd</a>    '] ==> 4

===================== finditer result =======================
('<a href="http://www.andylin02.com" target="_blank" class="dsdfv">aaaa</a>',)
------
('<a href="http://www.congfeng.com" target="_blank" class="tdsfv">bbbbsdf</a>',)
------
('<a href="http://www.st.com" target="_blank" class="txx">ccccccc</a>',)
------
('<a href="http://www.qs.com" target="_blank" class="xxx">ddddd</a>    ',)
------