Professional IronPython

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CHAPTER 5
InteractIng wIth StructureS and ObjectS
Performing Standard Tasks with Strings
You’ve already seen a few of the things you can do with strings in previous chapters. This chapter 
takes a little more organized look at the methods and properties associated with strings. The following 
list provides an overview of the most common tasks you can perform.
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center(int width[, Char fillchar])
: Centers the string within the space defined by 
width
. 
The default is to use spaces to pad the left and right side of the string to center it. However, you 
can specify another character by specifying the optional 
fillchar
. For example, if you want to 
center a string named MyString in a 40-character area using the * as a fill character, you’d type 
MyString.center(40, ‘*‘)
.
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int count(str ssub, [int start[, int end]])
: Counts the number of instances of 
a substring, 
ssub
, within a string. The substring can be one or more letters that you want 
to find within the string. You may optionally provide a starting point, 
start
, and an end-
ing point, 
end
, for the count. For example, if you want to count the number of ls found in 
MyString
, you’d type 
MyString.count(‘l‘, 0, len(MyString))
.
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decode([object encoding[, str errors]])
: Decodes an encoded string. Even
though 
encoding
is optional, you must provide a value in order to decode the string.
You can find a list of standard encodings at 
http://www.python.org/doc/2.5.2/lib/
standard-encodings.html
. The errors argument defines how 
decode()
treats errors, 
with a default value of 
strict
. You can find a list of error strings at 
http://www.python 
.org/doc/2.5.2/lib/codec-base-classes.html
. For example, you might have a Unix-
to-Unix Encode (uuencode) string named EncodeString that you want to decode into plain 
text. To convert the string, you’d type 
EncodeString.decode(‘uu_codec‘)
.
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