Ruby CSV.each用法及代码示例

each → enumerator

each {|row| ...}

用每个连续的行调用块。必须打开数据源才能读取。

没有标题：

string = "foo,0\nbar,1\nbaz,2\n"
csv = CSV.new(string)
csv.each do |row|
  p row
end

输出：

["foo", "0"]
["bar", "1"]
["baz", "2"]

带标题：

string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
csv = CSV.new(string, headers: true)
csv.each do |row|
  p row
end

输出：

<CSV::Row "Name":"foo" "Value":"0">
<CSV::Row "Name":"bar" "Value":"1">
<CSV::Row "Name":"baz" "Value":"2">

如果源未打开以供阅读，则引发异常：

string = "foo,0\nbar,1\nbaz,2\n"
csv = CSV.new(string)
csv.close
# Raises IOError (not opened for reading)
csv.each do |row|
  p row
end