Ruby使用正则表达式从字符串中提取数据

Question

我正在做一些网页抓取,这是数据的格式

Sr.No.  Course_Code Course_Name Credit  Grade   Attendance_Grade

我收到的实际字符串是以下形式

1 CA727 PRINCIPLES OF COMPILER DESIGN 3 A M

我感兴趣的东西是Course_Code,Course_Name和Grade,在这个例子中是值

Course_Code : CA727
Course_Name : PRINCIPLES OF COMPILER DESIGN
Grade : A

有没有办法让我使用正则表达式或其他技术轻松提取此信息,而不是手动解析字符串.我在1.9模式下使用jruby.

Answer 1

让我们使用Ruby的命名捕获和自我描述的正则表达式!

course_line = /
    ^                  # Starting at the front of the string
    (?<SrNo>\d+)       # Capture one or more digits; call the result "SrNo"
    \s+                # Eat some whitespace
    (?<Code>\S+)       # Capture all the non-whitespace you can; call it "Code"
    \s+                # Eat some whitespace
    (?<Name>.+\S)      # Capture as much as you can
                       # (while letting the rest of the regex still work)
                       # Make sure you end with a non-whitespace character.
                       # Call this "Name"
    \s+                # Eat some whitespace
    (?<Credit>\S+)     # Capture all the non-whitespace you can; call it "Credit"
    \s+                # Eat some whitespace
    (?<Grade>\S+)      # Capture all the non-whitespace you can; call it "Grade"
    \s+                # Eat some whitespace
    (?<Attendance>\S+) # Capture all the non-whitespace; call it "Attendance"
    $                  # Make sure that we're at the end of the line now
/x

str = "1   CA727   PRINCIPLES OF COMPILER DESIGN   3   A   M"
parts = str.match(course_line)

puts "
Course Code: #{parts['Code']}
Course Name: #{parts['Name']}
      Grade: #{parts['Grade']}".strip

#=> Course Code: CA727
#=> Course Name: PRINCIPLES OF COMPILER DESIGN
#=>       Grade: A

Answer 2

纯娱乐:

str = "1 CA727 PRINCIPLES OF COMPILER DESIGN 3 A M"
tok = str.split /\s+/
data = {'Sr.No.' => tok.shift, 'Course_Code' => tok.shift, 'Attendance_Grade' => tok.pop,'Grade' => tok.pop, 'Credit' => tok.pop, 'Course_Name' => tok.join(' ')}