Xquery 中的 Ascii 到十六进制转换

Question

我需要使用 XQuery 将 ASCII 转换为十六进制字符串，请帮助提供任何相应的参考或代码片段以实现此功能，例如我有字符串：1239565447854，我需要转换十六进制：31323339353635343437383534

Answer 1

您可以使用 string-to-codepoints() to get the numeric codepoint for each character. For each codepoint, determine how many times it is divisible by 16 using idiv, and the remainder using the mod 运算符。对于这两个数字，通过在 16 个字符的序列中按位置查找来获取它们的十六进制值，然后加入结果：

declare function local:codepoint-to-hex($codepoint as xs:integer) as xs:string {
  let $hex-index := ("0123456789ABCDEF" => string-to-codepoints()) ! codepoints-to-string(.)
  let $base16 := $codepoint idiv 16
  let $remainder := $codepoint mod 16
  return 
    string-join((
      $hex-index[$base16 + 1],
      if ($remainder = 0) 
      then ()
      else $hex-index[$remainder + 1]
      ), "")
};

declare function local:string-to-hex($str as xs:string) as xs:string {
  string-join( string-to-codepoints($str) ! local:codepoint-to-hex(.), "")
};

local:string-to-hex('1239565447854')

Xquery 中的 Ascii 到十六进制转换

Ascii to Hex conversion in Xquery

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