1.善于利用soup节点的parent属性
比如对于已经得到了如下html代码：
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<td style="padding-left:0" width="60%"><label>November</label>
<input type="Hidden" id="cboMonth1" name="cboMonth1" value="11">
</td><td style="padding-right:0;" width="40%">
<label>2012</label>
<input type="Hidden" id="cboYear1" name="cboYear1" value="2012">
</td>
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的soup变量eachMonthHeader了。
想要提取其中的
Month的label的值：November
和Year的label的值：2012
最简单，也是最省事的办法是，直接搜两个label，然后肯定会找到这两个label，然后分别对应着Month和Year的label，然后获得对应的string即可：
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foundTwoLabel = eachMonthHeader.findAll("label");
print "foundTwoLabel=",foundTwoLabel;
monthLabel = foundTwoLabel[0];
yearLabel = foundTwoLabel[1];
monthStr = monthLabel.string;
yearStr = yearLabel.string;
print "monthStr=",monthStr; # monthStr= November
print "yearStr=",yearStr; # yearStr= 2012
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但是很明显，这样的逻辑性很不好，而且万一处理多个这样的soup变量，而且两者的顺便颠倒了，那么结果也就错误了。
此时，可以考虑利用soup变量的parent属性，从一个soup变量本身，获得其上一级的soup变量。
示例代码如下：
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# <td style="padding-left:0" width="60%"><label>November</label>
# <input type="Hidden" id="cboMonth1" name="cboMonth1" value="11">
# </td><td style="padding-right:0;" width="40%">
# <label>2012</label>
# <input type="Hidden" id="cboYear1" name="cboYear1" value="2012">
# </td>
foundCboMonth = eachMonthHeader.find("input", {"id":re.compile("cboMonth\d+")});
#print "foundCboMonth=",foundCboMonth;
tdMonth = foundCboMonth.parent;
#print "tdMonth=",tdMonth;
tdMonthLabel = tdMonth.label;
#print "tdMonthLabel=",tdMonthLabel;
monthStr = tdMonthLabel.string;
print "monthStr=",monthStr;
foundCboYear = eachMonthHeader.find("input", {"id":re.compile("cboYear\d+")});
#print "foundCboYear=",foundCboYear;
tdYear = foundCboYear.parent;
#print "tdYear=",tdYear;
tdYearLabel = tdYear.label;
#print "tdYearLabel=",tdYearLabel;
yearStr = tdYearLabel.string;
print "yearStr=",yearStr;
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我们再来看一个例子：
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from BeautifulSoup import BeautifulSoup
doc = ['<html><head><title>Page title</title></head>',
'<body><p id="firstpara" align="center">This is paragraph <b>one</b>.',
'<p id="secondpara" align="blah">This is paragraph <b>two</b>.',
'</html>']
soup = BeautifulSoup(''.join(doc))
print soup.prettify()
# <html>
# <head>
# <title>
# Page title
# </title>
# </head>
# <body>
# <p id="firstpara" align="center">
# This is paragraph
# <b>
# one
# </b>
# .
# </p>
# <p id="secondpara" align="blah">
# This is paragraph
# <b>
# two
# </b>
# .
# </p>
# </body>
# </html>
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这个例子中，<HEAD> Tag的parent是<HTML> Tag. <HTML> Tag 的parent是BeautifulSoup 剖析对象自己。 剖析对象的parent是None. 利用parent，你可以向前遍历剖析树。
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soup.head.parent.name
# u'html'
soup.head.parent.parent.__class__.__name__
# 'BeautifulSoup'
soup.parent == None
# True
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2.当解析非UTF-8或ASCII编码类型的HTML时，需要指定对应的字符编码
当html为ASCII或UTF-8编码时，可以不指定html字符编码，便可正确解析html为对应的soup：
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#这里respHtml是ASCII或UTF-8编码，此时可以不指定编码类型，即可正确解析出对应的soup
soup = BeautifulSoup(respHtml);
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当html为其他类型编码，比如GB2312的话，则需要指定相应的字符编码，BeautifulSoup才能正确解析出对应的soup：
比如：
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#此处respHtml是GB2312编码的，所以要指定该编码类型，BeautifulSoup才能解析出对应的soup
htmlCharset = "GB2312";
soup = BeautifulSoup(respHtml, fromEncoding=htmlCharset);
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