28 lines
2.6 KiB
XML
28 lines
2.6 KiB
XML
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<?xml version="1.0"?>
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<clause number="9.4.1" title="Unicode escape sequences">
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<paragraph>A Unicode escape sequence represents a Unicode character. Unicode escape sequences are processed in identifiers (<hyperlink>9.4.2</hyperlink>), regular string literals (<hyperlink>9.4.4.5</hyperlink>), and character literals (<hyperlink>9.4.4.4</hyperlink>). A Unicode character escape is not processed in any other location (for example, to form an operator, punctuator, or keyword). <grammar_production><name><non_terminal where="9.4.1">unicode-escape-sequence</non_terminal></name> :: <rhs><terminal>\u</terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal></rhs><rhs><terminal>\U</terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal><non_terminal where="9.4.4.2">hex-digit</non_terminal></rhs></grammar_production></paragraph>
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<paragraph>A Unicode escape sequence represents the single Unicode character formed by the hexadecimal number following the "\u" or "\U" characters. Since C# uses a 16-bit encoding of Unicode characters in characters and string values, a Unicode character in the range U+10000 to U+10FFFF is represented using two Unicode surrogate characters. Unicode characters with code points above 0x10FFFF are not supported. </paragraph>
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<paragraph>Multiple translations are not performed. For instance, the string literal "\u005Cu005C" is equivalent to "\u005C" rather than "\". <note>[Note: The Unicode value \u005C is the character "\". end note]</note> </paragraph>
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<paragraph>
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<example>[Example: The example <code_example><![CDATA[
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class Class1
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{
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static void Test(bool \u0066) {
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char c = '\u0066';
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if (\u0066)
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System.Console.WriteLine(c.ToString());
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}
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}
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]]></code_example>shows several uses of \u0066, which is the escape sequence for the letter "f". The program is equivalent to <code_example><![CDATA[
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class Class1
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{
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static void Test(bool f) {
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char c = 'f';
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if (f)
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System.Console.WriteLine(c.ToString());
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}
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}
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]]></code_example>end example]</example>
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</paragraph>
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</clause>
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