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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="10.5.3.htm"><img src="previous.gif" alt="previous" border="0" /></a><a href="10.6.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="10.4.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.6.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="10.5.htm">10.5</a></span><span class="clause-title-previous"> Member access</span></span><span class="clause-depth"><a href="10.5.3.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.5.4.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number">10.5.4</span><span class="clause-title"> Accessibility constraints</span></span><span class="locator">
     Paragraph 1</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P1S1"></a>Several constructs in the C# language require a type to be at least as accessible as a member or another type.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P1S2"></a>A type T is said to be at least as accessible as a member or type M if the accessibility domain of T is a superset of the accessibility domain of M.</span> <span class="sentence"><span class="sentence-number">3</span> <a name="P1S3"></a>In other words, T is at least as accessible as M if T is accessible in all contexts in which M is accessible.</span> </span><span class="locator">
     Paragraph 2</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P2S1"></a>The following accessibility constraints exist: </span><ul><li><span class="sentence"><span class="sentence-number">2</span> <a name="P2S2"></a> The direct base class of a class type must be at least as accessible as the class type itself.</span> </li><li><span class="sentence"><span class="sentence-number">3</span> <a name="P2S3"></a> The explicit base interfaces of an interface type must be at least as accessible as the interface type itself.</span> </li><li><span class="sentence"><span class="sentence-number">4</span> <a name="P2S4"></a> The return type and parameter types of a delegate type must be at least as accessible as the delegate type itself.</span> </li><li><span class="sentence"><span class="sentence-number">5</span> <a name="P2S5"></a> The type of a constant must be at least as accessible as the constant itself.</span> </li><li><span class="sentence"><span class="sentence-number">6</span> <a name="P2S6"></a> The type of a field must be at least as accessible as the field itself.</span> </li><li><span class="sentence"><span class="sentence-number">7</span> <a name="P2S7"></a> The return type and parameter types of a method must be at least as accessible as the method itself.</span> </li><li><span class="sentence"><span class="sentence-number">8</span> <a name="P2S8"></a> The type of a property must be at least as accessible as the property itself.</span> </li><li><span class="sentence"><span class="sentence-number">9</span> <a name="P2S9"></a> The type of an event must be at least as accessible as the event itself.</span> </li><li><span class="sentence"><span class="sentence-number">10</span> <a name="P2S10"></a> The type and parameter types of an indexer must be at least as accessible as the indexer itself.</span> </li><li><span class="sentence"><span class="sentence-number">11</span> <a name="P2S11"></a> The return type and parameter types of an operator must be at least as accessible as the operator itself.</span> </li><li><span class="sentence"><span class="sentence-number">12</span> <a name="P2S12"></a> The parameter types of an instance constructor must be at least as accessible as the instance constructor itself.</span> </li></ul></span><span class="paragraph"><span class="example">[Example: In the example <pre class="code-example">
class A {...}  
public class B: A {...}  
</pre>the B class results in a compile-time error because A is not at least as accessible as B. end example]</span> </span><span class="paragraph"><span class="example">[Example: Likewise, in the example <pre class="code-example">
class A {...}  
public class B  
{  
   A F() {...}  
   internal A G() {...}  
   public A H() {...}  
}  
</pre>the H method in B results in a compile-time error because the return type A is not at least as accessible as the method. 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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