10.7.1.2.htm
来自「This ECMA Standard specifies the form an」· HTM 代码 · 共 36 行
HTM
36 行
<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="10.7.1.1.htm"><img src="previous.gif" alt="previous" border="0" /></a><a href="10.8.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="10.6.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.8.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="10.7.htm">10.7</a></span><span class="clause-title-previous"> Scopes</span></span><span class="clause-depth"><a href="10.7.1.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.7.1.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="10.7.1.htm">10.7.1</a></span><span class="clause-title-previous"> Name hiding</span></span><span class="clause-depth"><a href="10.7.1.1.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.7.1.2.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number">10.7.1.2</span><span class="clause-title"> Hiding through inheritance</span></span><span class="locator">
Paragraph 1</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P1S1"></a>Name hiding through inheritance occurs when classes or structs redeclare names that were inherited from base classes.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P1S2"></a>This type of name hiding takes one of the following forms: </span><ul><li><span class="sentence"><span class="sentence-number">3</span> <a name="P1S3"></a> A constant, field, property, event, or type introduced in a class or struct hides all base class members with the same name.</span> </li><li><span class="sentence"><span class="sentence-number">4</span> <a name="P1S4"></a> A method introduced in a class or struct hides all non-method base class members with the same name, and all base class methods with the same signature (method name and parameter count, modifiers, and types).</span> </li><li><span class="sentence"><span class="sentence-number">5</span> <a name="P1S5"></a> An indexer introduced in a class or struct hides all base class indexers with the same signature (parameter count and types).</span> </li></ul></span><span class="locator">
Paragraph 2</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P2S1"></a>The rules governing operator declarations (<a href="17.9.htm">§17.9</a>) make it impossible for a derived class to declare an operator with the same signature as an operator in a base class.</span> <span class="sentence"><span class="sentence-number">2</span> <a name="P2S2"></a>Thus, operators never hide one another.</span> </span><span class="locator">
Paragraph 3</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P3S1"></a>Contrary to hiding a name from an outer scope, hiding an accessible name from an inherited scope causes a warning to be reported.</span> <span class="example">[Example: In the example <pre class="code-example">
class Base
{
public void F() {}
}
class Derived: Base
{
public void F() {} // Warning, hiding an inherited name
}
</pre>the declaration of F in Derived causes a warning to be reported. Hiding an inherited name is specifically not an error, since that would preclude separate evolution of base classes. For example, the above situation might have come about because a later version of Base introduced an F method that wasn't present in an earlier version of the class. Had the above situation been an error, then any change made to a base class in a separately versioned class library could potentially cause derived classes to become invalid. end example]</span> </span><span class="locator">
Paragraph 4</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P4S1"></a>The warning caused by hiding an inherited name can be eliminated through use of the new modifier: </span><span class="example">[Example: <pre class="code-example">
class Base
{
public void F() {}
}
class Derived: Base
{
new public void F() {}
}
</pre></span></span><span class="paragraph"><span class="example">The new modifier indicates that the F in Derived is "new", and that it is indeed intended to hide the inherited member. end example]</span> </span><span class="paragraph"><span class="sentence"><span class="sentence-number">2</span> <a name="P4S2"></a>A declaration of a new member hides an inherited member only within the scope of the new member.</span> </span><span class="paragraph"><span class="example">[Example: <pre class="code-example">
class Base
{
public static void F() {}
}
class Derived: Base
{
new private static void F() {} // Hides Base.F in Derived only
}
class MoreDerived: Derived
{
static void G() { F(); } // Invokes Base.F
}
</pre></span></span><span class="paragraph"><span class="example">In the example above, the declaration of F in Derived hides the F that was inherited from Base, but since the new F in Derived has private access, its scope does not extend to MoreDerived. Thus, the call F() in MoreDerived.G is valid and will invoke Base.F. 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>⌨️ 快捷键说明
复制代码Ctrl + C
搜索代码Ctrl + F
全屏模式F11
增大字号Ctrl + =
减小字号Ctrl + -
显示快捷键?