<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Examples</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="errorfunc.constants.html">Predefined Constants</a></div> <div class="next" style="text-align: right; float: right;"><a href="ref.errorfunc.html">Error Handling Functions</a></div> <div class="up"><a href="book.errorfunc.html">Error Handling</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="errorfunc.examples" class="appendix"> <h1>Examples</h1> <p class="para"> Below we can see an example of using the error handling capabilities in PHP. We define an error handling function which logs the information into a file (using an XML format), and e-mails the developer if a critical error in the logic happens. <div class="example" id="example-448"> <p><strong>Example #1 Using error handling in a script</strong></p> <div class="example-contents"> <div class="phpcode"><code><span style="color: #000000"> <span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// we will do our own error handling<br /></span><span style="color: #0000BB">error_reporting</span><span style="color: #007700">(</span><span style="color: #0000BB">0</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// user defined error handling function<br /></span><span style="color: #007700">function </span><span style="color: #0000BB">userErrorHandler</span><span style="color: #007700">(</span><span style="color: #0000BB">$errno</span><span style="color: #007700">, </span><span style="color: #0000BB">$errmsg</span><span style="color: #007700">, </span><span style="color: #0000BB">$filename</span><span style="color: #007700">, </span><span style="color: #0000BB">$linenum</span><span style="color: #007700">, </span><span style="color: #0000BB">$vars</span><span style="color: #007700">) <br />{<br /> </span><span style="color: #FF8000">// timestamp for the error entry<br /> </span><span style="color: #0000BB">$dt </span><span style="color: #007700">= </span><span style="color: #0000BB">date</span><span style="color: #007700">(</span><span style="color: #DD0000">"Y-m-d H:i:s (T)"</span><span style="color: #007700">);<br /><br /> </span><span style="color: #FF8000">// define an assoc array of error string<br /> // in reality the only entries we should<br /> // consider are E_WARNING, E_NOTICE, E_USER_ERROR,<br /> // E_USER_WARNING and E_USER_NOTICE<br /> </span><span style="color: #0000BB">$errortype </span><span style="color: #007700">= array (<br /> </span><span style="color: #0000BB">E_ERROR </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Error'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_WARNING </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Warning'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_PARSE </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Parsing Error'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_NOTICE </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Notice'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_CORE_ERROR </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Core Error'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_CORE_WARNING </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Core Warning'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_COMPILE_ERROR </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Compile Error'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_COMPILE_WARNING </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Compile Warning'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_USER_ERROR </span><span style="color: #007700">=> </span><span style="color: #DD0000">'User Error'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_USER_WARNING </span><span style="color: #007700">=> </span><span style="color: #DD0000">'User Warning'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_USER_NOTICE </span><span style="color: #007700">=> </span><span style="color: #DD0000">'User Notice'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_STRICT </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Runtime Notice'</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">E_RECOVERABLE_ERROR </span><span style="color: #007700">=> </span><span style="color: #DD0000">'Catchable Fatal Error'<br /> </span><span style="color: #007700">);<br /> </span><span style="color: #FF8000">// set of errors for which a var trace will be saved<br /> </span><span style="color: #0000BB">$user_errors </span><span style="color: #007700">= array(</span><span style="color: #0000BB">E_USER_ERROR</span><span style="color: #007700">, </span><span style="color: #0000BB">E_USER_WARNING</span><span style="color: #007700">, </span><span style="color: #0000BB">E_USER_NOTICE</span><span style="color: #007700">);<br /> <br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">= </span><span style="color: #DD0000">"<errorentry>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<datetime>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$dt </span><span style="color: #007700">. </span><span style="color: #DD0000">"</datetime>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<errornum>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$errno </span><span style="color: #007700">. </span><span style="color: #DD0000">"</errornum>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<errortype>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$errortype</span><span style="color: #007700">[</span><span style="color: #0000BB">$errno</span><span style="color: #007700">] . </span><span style="color: #DD0000">"</errortype>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<errormsg>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$errmsg </span><span style="color: #007700">. </span><span style="color: #DD0000">"</errormsg>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<scriptname>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$filename </span><span style="color: #007700">. </span><span style="color: #DD0000">"</scriptname>\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<scriptlinenum>" </span><span style="color: #007700">. </span><span style="color: #0000BB">$linenum </span><span style="color: #007700">. </span><span style="color: #DD0000">"</scriptlinenum>\n"</span><span style="color: #007700">;<br /><br /> if (</span><span style="color: #0000BB">in_array</span><span style="color: #007700">(</span><span style="color: #0000BB">$errno</span><span style="color: #007700">, </span><span style="color: #0000BB">$user_errors</span><span style="color: #007700">)) {<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"\t<vartrace>" </span><span style="color: #007700">. </span><span style="color: #0000BB">wddx_serialize_value</span><span style="color: #007700">(</span><span style="color: #0000BB">$vars</span><span style="color: #007700">, </span><span style="color: #DD0000">"Variables"</span><span style="color: #007700">) . </span><span style="color: #DD0000">"</vartrace>\n"</span><span style="color: #007700">;<br /> }<br /> </span><span style="color: #0000BB">$err </span><span style="color: #007700">.= </span><span style="color: #DD0000">"</errorentry>\n\n"</span><span style="color: #007700">;<br /> <br /> </span><span style="color: #FF8000">// for testing<br /> // echo $err;<br /><br /> // save to the error log, and e-mail me if there is a critical user error<br /> </span><span style="color: #0000BB">error_log</span><span style="color: #007700">(</span><span style="color: #0000BB">$err</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">, </span><span style="color: #DD0000">"/usr/local/php4/error.log"</span><span style="color: #007700">);<br /> if (</span><span style="color: #0000BB">$errno </span><span style="color: #007700">== </span><span style="color: #0000BB">E_USER_ERROR</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">mail</span><span style="color: #007700">(</span><span style="color: #DD0000">"phpdev@example.com"</span><span style="color: #007700">, </span><span style="color: #DD0000">"Critical User Error"</span><span style="color: #007700">, </span><span style="color: #0000BB">$err</span><span style="color: #007700">);<br /> }<br />}<br /><br /><br />function </span><span style="color: #0000BB">distance</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect1</span><span style="color: #007700">, </span><span style="color: #0000BB">$vect2</span><span style="color: #007700">) <br />{<br /> if (!</span><span style="color: #0000BB">is_array</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect1</span><span style="color: #007700">) || !</span><span style="color: #0000BB">is_array</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect2</span><span style="color: #007700">)) {<br /> </span><span style="color: #0000BB">trigger_error</span><span style="color: #007700">(</span><span style="color: #DD0000">"Incorrect parameters, arrays expected"</span><span style="color: #007700">, </span><span style="color: #0000BB">E_USER_ERROR</span><span style="color: #007700">);<br /> return </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /> }<br /><br /> if (</span><span style="color: #0000BB">count</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect1</span><span style="color: #007700">) != </span><span style="color: #0000BB">count</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect2</span><span style="color: #007700">)) {<br /> </span><span style="color: #0000BB">trigger_error</span><span style="color: #007700">(</span><span style="color: #DD0000">"Vectors need to be of the same size"</span><span style="color: #007700">, </span><span style="color: #0000BB">E_USER_ERROR</span><span style="color: #007700">);<br /> return </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /> }<br /><br /> for (</span><span style="color: #0000BB">$i</span><span style="color: #007700">=</span><span style="color: #0000BB">0</span><span style="color: #007700">; </span><span style="color: #0000BB">$i</span><span style="color: #007700"><</span><span style="color: #0000BB">count</span><span style="color: #007700">(</span><span style="color: #0000BB">$vect1</span><span style="color: #007700">); </span><span style="color: #0000BB">$i</span><span style="color: #007700">++) {<br /> </span><span style="color: #0000BB">$c1 </span><span style="color: #007700">= </span><span style="color: #0000BB">$vect1</span><span style="color: #007700">[</span><span style="color: #0000BB">$i</span><span style="color: #007700">]; </span><span style="color: #0000BB">$c2 </span><span style="color: #007700">= </span><span style="color: #0000BB">$vect2</span><span style="color: #007700">[</span><span style="color: #0000BB">$i</span><span style="color: #007700">];<br /> </span><span style="color: #0000BB">$d </span><span style="color: #007700">= </span><span style="color: #0000BB">0.0</span><span style="color: #007700">;<br /> if (!</span><span style="color: #0000BB">is_numeric</span><span style="color: #007700">(</span><span style="color: #0000BB">$c1</span><span style="color: #007700">)) {<br /> </span><span style="color: #0000BB">trigger_error</span><span style="color: #007700">(</span><span style="color: #DD0000">"Coordinate </span><span style="color: #0000BB">$i</span><span style="color: #DD0000"> in vector 1 is not a number, using zero"</span><span style="color: #007700">, <br /> </span><span style="color: #0000BB">E_USER_WARNING</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$c1 </span><span style="color: #007700">= </span><span style="color: #0000BB">0.0</span><span style="color: #007700">;<br /> }<br /> if (!</span><span style="color: #0000BB">is_numeric</span><span style="color: #007700">(</span><span style="color: #0000BB">$c2</span><span style="color: #007700">)) {<br /> </span><span style="color: #0000BB">trigger_error</span><span style="color: #007700">(</span><span style="color: #DD0000">"Coordinate </span><span style="color: #0000BB">$i</span><span style="color: #DD0000"> in vector 2 is not a number, using zero"</span><span style="color: #007700">, <br /> </span><span style="color: #0000BB">E_USER_WARNING</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$c2 </span><span style="color: #007700">= </span><span style="color: #0000BB">0.0</span><span style="color: #007700">;<br /> }<br /> </span><span style="color: #0000BB">$d </span><span style="color: #007700">+= </span><span style="color: #0000BB">$c2</span><span style="color: #007700">*</span><span style="color: #0000BB">$c2 </span><span style="color: #007700">- </span><span style="color: #0000BB">$c1</span><span style="color: #007700">*</span><span style="color: #0000BB">$c1</span><span style="color: #007700">;<br /> }<br /> return </span><span style="color: #0000BB">sqrt</span><span style="color: #007700">(</span><span style="color: #0000BB">$d</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #0000BB">$old_error_handler </span><span style="color: #007700">= </span><span style="color: #0000BB">set_error_handler</span><span style="color: #007700">(</span><span style="color: #DD0000">"userErrorHandler"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// undefined constant, generates a warning<br /></span><span style="color: #0000BB">$t </span><span style="color: #007700">= </span><span style="color: #0000BB">I_AM_NOT_DEFINED</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// define some "vectors"<br /></span><span style="color: #0000BB">$a </span><span style="color: #007700">= array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">, </span><span style="color: #DD0000">"foo"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$b </span><span style="color: #007700">= array(</span><span style="color: #0000BB">5.5</span><span style="color: #007700">, </span><span style="color: #0000BB">4.3</span><span style="color: #007700">, -</span><span style="color: #0000BB">1.6</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$c </span><span style="color: #007700">= array(</span><span style="color: #0000BB">1</span><span style="color: #007700">, -</span><span style="color: #0000BB">3</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// generate a user error<br /></span><span style="color: #0000BB">$t1 </span><span style="color: #007700">= </span><span style="color: #0000BB">distance</span><span style="color: #007700">(</span><span style="color: #0000BB">$c</span><span style="color: #007700">, </span><span style="color: #0000BB">$b</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// generate another user error<br /></span><span style="color: #0000BB">$t2 </span><span style="color: #007700">= </span><span style="color: #0000BB">distance</span><span style="color: #007700">(</span><span style="color: #0000BB">$b</span><span style="color: #007700">, </span><span style="color: #DD0000">"i am not an array"</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// generate a warning<br /></span><span style="color: #0000BB">$t3 </span><span style="color: #007700">= </span><span style="color: #0000BB">distance</span><span style="color: #007700">(</span><span style="color: #0000BB">$a</span><span style="color: #007700">, </span><span style="color: #0000BB">$b</span><span style="color: #007700">) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">?></span> </span> </code></div> </div> </div> </p> </div> <hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="errorfunc.constants.html">Predefined Constants</a></div> <div class="next" style="text-align: right; float: right;"><a href="ref.errorfunc.html">Error Handling Functions</a></div> <div class="up"><a href="book.errorfunc.html">Error Handling</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>