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📁 This ECMA Standard specifies the form and establishes the interpretation of programs written in the
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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>Hyperlinked ECMA C# Language Specification</title><meta name="author" content="Jon Jagger" /><link rel="stylesheet" href="ecma334.css"></link></head><body><div align="right"><em><a href="http://www.jaggersoft.com">Jon Jagger</a></em></div><div align="right"><a href="mailto:jon@jaggersoft.com">jon@jaggersoft.com</a></div><form method="get" action="http://search.atomz.com/search/"><input size="30" name="sp-q"></input><input type="submit" value="Search C# Spec"></input><input type="hidden" name="sp-a" value="sp10024177"></input><input type="hidden" name="sp-f" value="ISO-8859-1"></input></form><a href="toc.htm">Table of Contents</a> <a href="1.htm">1</a> <a href="2.htm">2</a> <a href="3.htm">3</a> <a href="4.htm">4</a> <a href="5.htm">5</a> <a href="6.htm">6</a> <a href="7.htm">7</a> <a href="8.htm">8</a> <a href="9.htm">9</a> <a href="10.htm">10</a> <a href="11.htm">11</a> <a href="12.htm">12</a> <a href="13.htm">13</a> <a href="14.htm">14</a> <a href="15.htm">15</a> <a href="16.htm">16</a> <a href="17.htm">17</a> <a href="18.htm">18</a> <a href="19.htm">19</a> <a href="20.htm">20</a> <a href="21.htm">21</a> <a href="22.htm">22</a> <a href="23.htm">23</a> <a href="24.htm">24</a> <a href="25.htm">25</a> <a href="notes.htm">Notes</a> <a href="HyperlinkedCSharpECMA.zip">Download</a><span class="ruler"></span><span class="heading">ECMA-334 C# Language Specification</span><span class="navigate"><a href="10.htm"><img src="previous.gif" alt="previous" border="0" /></a><a href="10.2.htm"><img src="next.gif" alt="next" border="0" /></a></span><span class="clause-depth"><a href="9.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="11.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="10.htm">10</a></span><span class="clause-title-previous"> Basic concepts</span></span><span class="clause-depth"><a href="10.1.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.2.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number">10.1</span><span class="clause-title"> Application startup</span></span><span class="locator">
     Paragraph 1</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P1S1"></a>Application startup occurs when the execution environment calls a designated method, which is referred to as the application's entry point.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P1S2"></a>This entry point method is always named Main, and shall have one of the following signatures: <pre class="code-example">
static void Main() {...}  
static void Main(string[] args) {...}  
static int Main() {...}  
static int Main(string[] args) {...}  
</pre></span></span><span class="locator">
     Paragraph 2</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P2S1"></a>As shown, the entry point may optionally return an <span class="keyword">int</span> value.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P2S2"></a>This return value is used in application termination (<a href="10.2.htm">&#167;10.2</a>).</span> </span><span class="locator">
     Paragraph 3</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P3S1"></a>The entry point may optionally have one formal parameter, and this formal parameter may have any name.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P3S2"></a>If such a parameter is declared, it must obey the following constraints: </span><ul><li><span class="sentence"><span class="sentence-number">3</span> <a name="P3S3"></a> The implementation shall ensure that the value of this parameter is not null.</span> </li><li><span class="sentence"><span class="sentence-number">4</span> <a name="P3S4"></a> Let args be the name of the parameter.</span> <span class="sentence"><span class="sentence-number">5</span> <a name="P3S5"></a>If the length of the array designated by args is greater than zero, the array members args[0] through args[args.Length-1], inclusive, must refer to strings, called application parameters, which are given implementation-defined values by the host environment prior to application startup.</span> <span class="sentence"><span class="sentence-number">6</span> <a name="P3S6"></a>The intent is to supply to the application information determined prior to application startup from elsewhere in the hosted environment.</span> <span class="sentence"><span class="sentence-number">7</span> <a name="P3S7"></a>If the host environment is not capable of supplying strings with letters in both uppercase and lowercase, the implementation shall ensure that the strings are received in lowercase.</span> <span class="note">[Note: On systems supporting a command line, application parameters correspond to what are generally known as command-line arguments. end note]</span> </li></ul></span><span class="locator">
     Paragraph 4</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P4S1"></a>Since C# supports method overloading, a class or struct may contain multiple definitions of some method, provided each has a different signature.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P4S2"></a>However, within a single program, no class or struct shall contain more than one method called Main whose definition qualifies it to be used as an application entry point.</span> <span class="sentence"><span class="sentence-number">3</span> <a name="P4S3"></a>Other overloaded versions of Main are permitted, however, provided they have more than one parameter, or their only parameter is other than type string[].</span> </span><span class="locator">
     Paragraph 5</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P5S1"></a>An application can be made up of multiple classes or structs.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P5S2"></a>It is possible for more than one of these classes or structs to contain a method called Main whose definition qualifies it to be used as an application entry point.</span> <span class="sentence"><span class="sentence-number">3</span> <a name="P5S3"></a>In such cases, one of these Main methods must be chosen as the entry point so that application startup can occur.</span> <span class="sentence"><span class="sentence-number">4</span> <a name="P5S4"></a>This choice of an entry point is beyond the scope of this specification-no mechanism for specifying or determining an entry point is provided.</span> </span><span class="locator">
     Paragraph 6</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P6S1"></a>In C#, every method must be defined as a member of a class or struct.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P6S2"></a>Ordinarily, the declared accessibility (<a href="10.5.1.htm">&#167;10.5.1</a>) of a method is determined by the access modifiers (<a href="17.2.3.htm">&#167;17.2.3</a>) specified in its declaration, and similarly the declared accessibility of a type is determined by the access modifiers specified in its declaration.</span> <span class="sentence"><span class="sentence-number">3</span> <a name="P6S3"></a>In order for a given method of a given type to be callable, both the type and the member must be accessible.</span> <span class="sentence"><span class="sentence-number">4</span> <a name="P6S4"></a>However, the application entry point is a special case.</span> <span class="sentence"><span class="sentence-number">5</span> <a name="P6S5"></a>Specifically, the execution environment can access the application's entry point regardless of its declared accessibility and regardless of the declared accessibility of its enclosing type declarations.</span> </span><span class="locator">
     Paragraph 7</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P7S1"></a>In all other respects, entry point methods behave like those that are not entry points.</span> </span><span class="ruler"></span><table><tr><td><table align="left" bgcolor="navy"><tr bgcolor="navy"><td><font face="Arial,sans-serif" size="6" color="yellow"><strong>{ JSL }</strong></font></td></tr></table></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>Jagger Software Ltd</strong></font></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>Company # 4070126</strong></font></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>VAT # 762 5213 42</strong></font></td></tr></table><img src="valid-html401.png" align="left" height="31" width="88" alt="Valid HTML 4.01" /><img src="vcss.gif" align="left" height="31" width="88" alt="Valid CSS" /></body></html>
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