function.file-exists.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Checks whether a file or directory exists</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.fgetss.html">fgetss</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.file-get-contents.html">file_get_contents</a></div> <div class="up"><a href="ref.filesystem.html">Filesystem Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.file-exists" class="refentry"> <div class="refnamediv"> <h1 class="refname">file_exists</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">file_exists</span> — <span class="dc-title">Checks whether a file or directory exists</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">bool</span> <span class="methodname"><b><b>file_exists</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$filename</tt></span> )</div> <p class="para rdfs-comment"> Checks whether a file or directory exists. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">filename</tt></i></span> <dd> <p class="para"> Path to the file or directory. </p> <p class="para"> On windows, use <var class="filename">//computername/share/filename</var> or <var class="filename">\\computername\share\filename</var> to check files on network shares. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns <b><tt>TRUE</tt></b> if the file or directory specified by <i><tt class="parameter">filename</tt></i> exists; <b><tt>FALSE</tt></b> otherwise. </p> <blockquote><p><b class="note">Note</b>: This function will return <b><tt>FALSE</tt></b> for symlinks pointing to non-existing files. <br /> </p></blockquote> <div class="warning"><b class="warning">Warning</b> <p class="para"> This function returns <b><tt>FALSE</tt></b> for files inaccessible due to <a href="features.safe-mode.html" class="link">safe mode</a> restrictions. However these files still can be <a href="function.include.html" class="link">included</a> if they are located in <a href="features.safe-mode.html#ini.safe-mode-include-dir" class="link">safe_mode_include_dir</a>. </p> </div> <blockquote><p><b class="note">Note</b>: The check is done using the real UID/GID instead of the effective one. <br /> </p></blockquote> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 Testing whether a file exists</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$filename </span><span style="color: #007700">= </span><span style="color: #DD0000">'/path/to/foo.txt'</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">file_exists</span><span style="color: #007700">(</span><span style="color: #0000BB">$filename</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"The file $filename exists"</span><span style="color: #007700">;<br />} else {<br /> echo </span><span style="color: #DD0000">"The file $filename does not exist"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <blockquote><p><b class="note">Note</b>: <span class="simpara">The results of this function are cached. See <a href="function.clearstatcache.html" class="function">clearstatcache()</a> for more details.</span></p></blockquote> <div class="tip"><b class="tip">Tip</b><p class="simpara">As of PHP 5.0.0, this functioncan also be used with <em class="emphasis">some</em> URL wrappers. Refer to <a href="wrappers.html" class="xref">List of Supported Protocols/Wrappers</a> for a listing of which wrappers support <a href="function.stat.html" class="function">stat()</a> family of functionality.</p></div> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.is-readable.html" class="function" rel="rdfs-seeAlso">is_readable()</a></li> <li class="member"><a href="function.is-writable.html" class="function" rel="rdfs-seeAlso">is_writable()</a></li> <li class="member"><a href="function.is-file.html" class="function" rel="rdfs-seeAlso">is_file()</a></li> <li class="member"><a href="function.file.html" class="function" rel="rdfs-seeAlso">file()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.fgetss.html">fgetss</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.file-get-contents.html">file_get_contents</a></div> <div class="up"><a href="ref.filesystem.html">Filesystem Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
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