文字列操作の比較表 - Ruby, PHP, Objective-C

Ruby (String)	PHP (String 非オブジェクト)	Objective-C (NSString)
s = "abc"	$s = "abc"	s = @"abc"
s = x + y	$s = $x . $y	s = [x stringByAppendingString:y]
s == x	$s == $x	[s isEqualToString:x]
s % [x, y] sprintf(s, x, y)	sprintf($s, $x, $y)	[NSString stringWithFormat:s, x, y]
[x, y, z].join(d)	implode($d, $a) join($d, $a)	[a componentsJoinedByString:d] //NSArray
s.capitalize	ucfirst($s) ucwords($s)	[s capitalizedString]
s.capitalize!	↑	↑
s.center(w)	str_pad($s, $w, STR_PAD_BOTH)
s.chomp	rtrim(s, "\n")
s.chomp!	↑
s.chop
s.chop!
s.clear #1.9		[ms setString:@""]
s.concat(x)	$s .= $x	[ms appendString:x] s = [s stringByAppendingString:x]
s.count(x)	preg_match や preg_match_all で
s.crypt(x)	crypt($s, $x)	C で
s.delete(x)	str_replace($x, '', $s) preg_replace($x, '', $s)	OgreKitで？
s.downcase	strtolower($s)	[s lowercaseString]
s.downcase!	↑	↑
s.each_byte {|x| ... }	for($i=0; $x=$s[$i]; $i++){ ... }	[s cString] →後はお好きに
s.each_line {|x| ... }	implode して foreach？	[s componentsSeparatedByString:@"\n"]→for{}
s.empty?	strlen($s)==0	[s length]==0
s.end_with(x) #1.9
s.gsub(f, t)	str_replace($f, $t, $s) preg_replace($f, $t, $s)	OgreKitで？
s.gsub!(x, y)	↑
s.hex s.to_i(16)
s.include?(x)	strpos($s, $x)!==FALSE
s.index(x)	strpos($s, $x) //単純な文字列のみ
s.insert(i, x)
s.length s.size	strlen($s)	[s length]
s.ljust(w)	str_pad($s, $w, STR_PAD_RIGHT)
s.lstrip	ltrim(s)
s.lstrip!	↑
s.match(x) x.match(s)	preg_match($x, $s)	OgreKitで？
s.next! s.succ!	$s++ //けっこう賢い
s.oct s.to_i(8)
s.partition(x) #1.9
s.replace(x)	$s=$x	[ms setString:x]
s.reverse
s.reverse!
s.rindex(x)	strrpos($s, $x) //単純な文字列のみ
s.rjust(w)	str_pad($s, $w, STR_PAD_LEFT)
s.rpartition(x) #1.9
s.rstrip	rtrim(s)
s.rstrip!	↑
s.scan(x) { ... }
s[i] s.slice(i)	$s[i] substr($s, $i, 1)	[s substringWithRange:NSMakeRange(i, 1)]
s[i..-1] s.slice(i..-1)	substr($s, $i)	[s substringFromIndex:i]
s[i, l] s.slice(i, l)	substr($s, $i, $l)	[s substringWithRange:NSMakeRange(i, l)]
s[i..j] s.slice(i..j)	substr($s, $i, $j-$i+1)	[s substringWithRange:NSMakeRange(i, j-i+1)]
s[i...j] s.slice(i...j)	substr($s, $i, $j-$i)	[s substringWithRange:NSMakeRange(i, j-i)]
s.split(d)	explode($d, $s) //単純分割 preg_split($d, $s)	[s componentsSeparatedByString:d] //単純分割
s.start_with(x) #1.9
s.strip	trim(s)	[s stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet] ]
s.strip!	↑	↑
s.sub(x, y)
s.sub!(x, y)
s.swapcase
s.to_f	floatval($s)	[s floatValue]
s.to_i	intval($s)	[s intValue]
s.tr!(x, y)	str_replace($x, $y, $s) preg_replace($x, $y, $s)
s.tr_s!(x, y)
s.unpack(x)	unserialize(s)	[s propertyList] [s propertyListFromStringsFileFormat]
s.upcase	strtoupper(s)	[s uppercaseString]
s.upcase!	↑	↑
Regexp.escape(s) Regexp.quote(s)	preg_quote($s) quotemeta($s)