字符串处理函数
1.返回字符串的长度
str.length => integer
2.判断字符串中是否包含另一个串
str.include? other_str => true or false "hello".include? "lo" #=> true "hello".include? "ol" #=> false "hello".include? ?h #=> true
3.字符串插入:
str.insert(index, other_str) => str "abcd".insert(0, 'X') #=> "Xabcd" "abcd".insert(3, 'X') #=> "abcXd" "abcd".insert(4, 'X') #=> "abcdX" "abcd".insert(-3, 'X') -3, 'X') #=> "abXcd" "abcd".insert(-1, 'X') #=> "abcdX"
4.字符串分隔,默认分隔符为空格
str.split(pattern=$;, [limit]) => anArray " now's the time".split #=> ["now's", "the", "time"] "1, 2.34,56, 7".split(%r{,s*}) #=> ["1", "2.34", "56", "7"] "hello".split(//) #=> ["h", "e", "l", "l", "o"] "hello".split(//, 3) #=> ["h", "e", "llo"] "hi mom".split(%r{s*}) #=> ["h", "i", "m", "o", "m"] "mellow yellow".split("ello") #=> ["m", "w y", "w"] "1,2,,3,4,,".split(',') #=> ["1", "2", "", "3", "4"] "1,2,,3,4,,".split(',', 4) #=> ["1", "2", "", "3,4,,"]
5.字符串替换
str.gsub(pattern, replacement) => new_str str.gsub(pattern) {|match| block } => new_str "hello".gsub(/[aeiou]/, '*') #=> "h*ll*" #将元音替换成*号 "hello".gsub(/([aeiou])/, '<1>') #=> "h<e>ll<o>" #将元音加上尖括号,1表示保留原有字符??? "hello".gsub(/./) {|s| s[0].to_s + ' '} #=> "104 101 108 108 111 "
字符串替换二:
str.replace(other_str) => str s = "hello" #=> "hello" s.replace "world" #=> "world"
6.字符串删除:
str.delete([other_str]+) => new_str "hello".delete "l","lo" #=> "heo" "hello".delete "lo" #=> "he" "hello".delete "aeiou", "^e" #=> "hell" "hello".delete "ej-m" #=> "ho"
7.去掉前和后的空格
str.lstrip => new_str " hello ".lstrip #=> "hello " "hello".lstrip #=> "hello"
8.字符串匹配
str.match(pattern) => matchdata or nil
9.字符串反转
str.reverse => new_str "stressed".reverse #=> "desserts"
10.去掉重复的字符
str.squeeze([other_str]*) => new_str "yellow moon".squeeze #=> "yelow mon" #默认去掉串中所有重复的字符 " now is the".squeeze(" ") #=> " now is the" #去掉串中重复的空格 "putters shoot balls".squeeze("m-z") #=> "puters shot balls" #去掉指定范围内的重复字符
11.转化成数字
str.to_i=> str "12345".to_i #=> 12345
chomp和chop的区别:
chomp:去掉字符串末尾的
或
chop:去掉字符串末尾的最后一个字符,不管是
还是普通字符
"hello".chomp #=> "hello" "hello ".chomp #=> "hello" "hello ".chomp #=> "hello" "hello ".chomp #=> "hello " "hello ".chomp #=> "hello" "hello".chomp("llo") #=> "he" "string ".chop #=> "string" "string ".chop #=> "string " "string ".chop #=> "string" "string".chop #=> "strin"
转载自：http://blog.163.com/ma95221@126/blog/static/2482210220100159515220/