blocks|key|1383662|text|我不知道你在找什么，你是说find()吗？|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1383663|>>>+x+=+"Hello+World"
>>>+x.find('World')
6
>>>+x.find('Aloha');
-1|code-block|syntax|javascript|1383664|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/library/stdtypes.html#str.find^0|D|6|D|6|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

I'm not sure what you're looking for, do you mean <a href="http://docs.python.org/library/stdtypes.html#str.find" rel="noreferrer"><code>find()</code></a>?

<pre><code>&gt;&gt;&gt; x = "Hello World"
&gt;&gt;&gt; x.find('World')
6
&gt;&gt;&gt; x.find('Aloha');
-1
</code></pre>

blocks|key|1383685|text|您也可以使用str.index：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1383686|>>>+'sdfasdf'.index('cc')
Traceback+(most+recent+call+last):
++File+"<pyshell#144>",+line+1,+in+<module>
++++'sdfasdf'.index('cc')
ValueError:+substring+not+found
>>>+'sdfasdf'.index('df')
1|code-block|syntax|javascript|1383687|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/library/stdtypes.html?highlight=index#str.index^0|6|9|6|9|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

you can use <a href="http://docs.python.org/library/stdtypes.html?highlight=index#str.index" rel="noreferrer"><code>str.index</code></a> too:

<pre><code>&gt;&gt;&gt; 'sdfasdf'.index('cc')
Traceback (most recent call last):
 File "&lt;pyshell#144&gt;", line 1, in &lt;module&gt;
 'sdfasdf'.index('cc')
ValueError: substring not found
&gt;&gt;&gt; 'sdfasdf'.index('df')
1
</code></pre>

blocks|key|1598707|text|find(++++++sub[,+start[,+end]])|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1598708|返回字符串中找到sub的最低索引，这样sub就包含在start，end范围内。可选参数start和end被解释为切片表示法。如果找不到sub，则返回-1。|1598709|来自the+docs。|1598710|entityMap|0|LINK|mutability|MUTABLE|url|http://www.python.org/doc/2.4.4/lib/string-methods.html^0|0|V|0|0|2|8|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@$9|S|A|T|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|U|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|V|8|@]|D|@$9|W|A|X|1|Y]]|E|$]]|$1|J|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|K|$L|$5|M|N|O|E|$P|Q]]]]

<code>find( sub[, start[, end]])</code>

Return the lowest index in the string where substring sub is found, such that sub is contained in the range [start, end]. Optional arguments start and end are interpreted as in slice notation. Return -1 if sub is not found. 

From <a href="http://www.python.org/doc/2.4.4/lib/string-methods.html" rel="nofollow noreferrer">the docs</a>.

blocks|key|1598767|text|老实说，这就是我在命令行上打开Python并开始胡乱操作的那种情况：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1598768|+>>>+x+=+"Dana+Larose+is+playing+with+find()"
+>>>+x.find("Dana")
+0
+>>>+x.find("ana")
+1
+>>>+x.find("La")
+5
+>>>+x.find("La",+6)
+-1|code-block|syntax|javascript|1598769|Python的解释器使得这种实验变得很容易。(具有类似解释器的其他语言也是如此)|1598770|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Honestly, this is the sort of situation where I just open up Python on the command line and start messing around:

<pre><code> &gt;&gt;&gt; x = "Dana Larose is playing with find()"
 &gt;&gt;&gt; x.find("Dana")
 0
 &gt;&gt;&gt; x.find("ana")
 1
 &gt;&gt;&gt; x.find("La")
 5
 &gt;&gt;&gt; x.find("La", 6)
 -1
</code></pre>

Python's interpreter makes this sort of experimentation easy. (Same goes for other languages with a similar interpreter)

blocks|key|1383928|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1383929|with+open(file_dmp_path,+'rb')+as+file:
fsize+=+bsize+=+os.path.getsize(file_dmp_path)
word_len+=+len(SEARCH_WORD)
while+True:
++++p+=+file.read(bsize).find(SEARCH_WORD)
++++if+p+>+-1:
++++++++pos_dec+=+file.tell()+-+(bsize+-+p)
++++++++file.seek(pos_dec+%2B+word_len)
++++++++bsize+=+fsize+-+file.tell()
++++if+file.tell()+<+fsize:
++++++++seek+=+file.tell()+-+word_len+%2B+1
++++++++file.seek(seek)
++++else:
++++++++break|code-block|syntax|javascript|1383930|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Try this:

<pre><code>with open(file_dmp_path, 'rb') as file:
fsize = bsize = os.path.getsize(file_dmp_path)
word_len = len(SEARCH_WORD)
while True:
 p = file.read(bsize).find(SEARCH_WORD)
 if p &gt; -1:
 pos_dec = file.tell() - (bsize - p)
 file.seek(pos_dec + word_len)
 bsize = fsize - file.tell()
 if file.tell() &lt; fsize:
 seek = file.tell() - word_len + 1
 file.seek(seek)
 else:
 break
</code></pre>

blocks|key|1598950|text|试一试|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1598951|myString+=+'abcabc'
myString.find('a')|code-block|syntax|javascript|1598952|这将为您提供索引！|1598953|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Try
<pre><code>myString = 'abcabc'
myString.find('a')
</code></pre>
This will give you the index!!!

I am trying to find some examples but no luck. Does anyone know of some examples on the net? I would like to know what it returns when it can't find, and how to specify from start to end, which I guess is going to be 0, -1.

Examples for string find in Python

解释器

Python

我正在试着找一些例子，但没有运气。有人知道网上的一些例子吗？我想知道当它找不到的时候返回什么，以及如何从头到尾指定，我猜应该是0，-1。

问Python中的字符串查找示例
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