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  • ruby 字符串学习笔记3

    ascii转字符或者字符串转ascii

    "a".ord # =>  97
    "!".ord  # => 33
    "
    ".ord # => 10
    'a'[0] # => "a"
    'bad sound'[1]  # => "a"
    
    'a'[0].ord # => 97
    'bad sound'[1].ord  # => 97
    97.chr  # => "a"

    符号转字符串

    :a_symbol.to_s # => "a_symbol"
    :AnotherSymbol.id2name  # => "AnotherSymbol"
    :"Yet another symbol!".to_s # => "Yet another symbol!"

    通过字符串得到相应的符号

    :dodecahedron.object_id # => 516488
    symbol_name = "dodecahedron"
    symbol_name.intern # => :dodecahedron
    symbol_name.intern.object_id # => 516488

    符号由一个名字和一个internal id 组成,相同符号引用同一个对象,但是两个内容一样的字符串却是不同的对象

    "string".object_id   # =>70309575257960
    "string".object_id   # =>70309575257221
    :symbol.object_id  # => 87690
    :symbol.object_id  # => 87690

    如果对象内容重要使用字符串,如果对象唯一性重要使用符号

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  • 原文地址:https://www.cnblogs.com/or2-/p/5008212.html
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