如何在Ruby中的字符串开头添加一定数量的空格？

Question

我正在使用Ruby 2.3.如何在字符串的开头添加一定数量的空格？我认为rjust是这样做的,但是当我想在字符串的前面添加1个填充空间时,这些调用什么都不做.

line = "  29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"
# => "  29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha" 
line.rjust(1)
# => "  29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"

Answer 1

尝试

line = "  29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"
#=> "  29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"
line.prepend(" ")
#=> "   29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"
line.prepend(" " * 2) # for a variable number of spaces
#=> "    29  25  13 M10-19 14    23:36  7:36    826 HYLLBERG MARCO      WI Kenosha"