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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="24.1.1.htm"><img src="previous.gif" alt="previous" border="0" /></a><a href="24.1.3.htm"><img src="next.gif" alt="next" border="0" /></a></span><span class="clause-depth"><a href="23.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="25.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="24.htm">24</a></span><span class="clause-title-previous"> Attributes</span></span><span class="clause-depth"><a href="24.1.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="24.2.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="24.1.htm">24.1</a></span><span class="clause-title-previous"> Attribute classes</span></span><span class="clause-depth"><a href="24.1.1.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="24.1.3.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number">24.1.2</span><span class="clause-title"> Positional and named parameters</span></span><span class="locator">
     Paragraph 1</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P1S1"></a>Attribute classes can have positional parameters and named parameters.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P1S2"></a>Each public instance constructor for an attribute class defines a valid sequence of positional parameters for that attribute class.</span> <span class="sentence"><span class="sentence-number">3</span> <a name="P1S3"></a>Each  non-static public read-write field and property for an attribute class defines a named parameter for the attribute class.</span> </span><span class="paragraph"><span class="example">[Example: The example <pre class="code-example">
using System;  
[AttributeUsage(AttributeTargets.Class)]  
public class HelpAttribute: Attribute  
{  
   public HelpAttribute(string url) {  // url is a positional parameter  
      ...  
   }  
   public string Topic {  // Topic is a named parameter  
      get {...}  
      set {...}  
   }  
   public string Url { get {...} }  
}  
</pre>defines an attribute class named HelpAttribute that has one positional parameter (string url) and one named parameter (string Topic). Although it is non-static and public, the property Url does not define a named parameter, since it is not read-write. </span></span><span class="paragraph"><span class="example">This attribute class might be used as follows: <pre class="code-example">
[Help("http://www.mycompany.com/.../Class1.htm")]  
class Class1 {  
}  
[Help("http://www.mycompany.com/.../Misc.htm", Topic ="Class2")]  
class Class2 {  
}  
</pre>end example]</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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