28 lines
1.6 KiB
XML
28 lines
1.6 KiB
XML
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<?xml version="1.0"?>
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<clause number="8.2.2" title="Conversions" informative="true">
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<paragraph>The predefined types also have predefined conversions. For instance, conversions exist between the predefined types <keyword>int</keyword> and <keyword>long</keyword>. C# differentiates between two kinds of conversions: implicit conversions and explicit conversions. Implicit conversions are supplied for conversions that can safely be performed without careful scrutiny. For instance, the conversion from <keyword>int</keyword> to <keyword>long</keyword> is an implicit conversion. This conversion always succeeds, and never results in a loss of information. The following example <code_example><![CDATA[
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using System;
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class Test
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{
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static void Main() {
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int intValue = 123;
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long longValue = intValue;
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Console.WriteLine("{0}, {1}", intValue, longValue);
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}
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}
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]]></code_example>implicitly converts an <keyword>int</keyword> to a <keyword>long</keyword>. </paragraph>
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<paragraph>In contrast, explicit conversions are performed with a cast expression. The example <code_example><![CDATA[
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using System;
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class Test
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{
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static void Main() {
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long longValue = Int64.MaxValue;
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int intValue = (int) longValue;
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Console.WriteLine("(int) {0} = {1}", longValue, intValue);
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}
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}
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]]></code_example>uses an explicit conversion to convert a <keyword>long</keyword> to an <keyword>int</keyword>. The output is: <code_example><![CDATA[
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(int) 9223372036854775807 = -1
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]]></code_example>because an overflow occurs. Cast expressions permit the use of both implicit and explicit conversions. </paragraph>
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</clause>
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