Finally the environment is configured, try PHP! Where should I write the code? <% code %> code </script?></p> <p> </p> <p>Mark the author and make comments?<br> //author : matter</p> <p>/*</p> <p> *author : matter</p> <p> */</p> <p>#author : matter</p> <p> </p> <p>It finally officially started, ok, let’s go directly to the classic case<br> <?php echo 'Goodbye world~'; ?></p> <p><?php echo "Goodbye world~"; ?></p> <p><?php print "Goodbye world"; ?></p> <p><?php printf("Goodbye World") ; ?></p> <p>Pay attention to the discolored parts</p> <p>Single quotes are OK, double quotes are also OK<br> Single quotes have incomplete support for escape characters!<br> Echo can be used, print can be used, and printf can also be used <br> Why do you add parentheses to printf? <br> The brackets for echo() and print() can be omitted <br> Is there a difference between echo and print?<br> echo() has no return value, print() successfully outputs and returns 1<br> So it can be seen that echo() is faster than print()!<br> Use printf for dynamic text, and echo<br> for static text. $test=sprintf("$%.2f",12.3424);</p> <p>printf("Goodbye-- World,$test");</p> <p>sprintf can assign values to variables~</p> <p> </p> <p>It’s time to show me variables!<br> Weakly typed language --- Everything is scalar</p> <p>$myVar = "anything";</p> <p>Array</p> <p>$arr[0] = "abc";</p> <p> </p> <p>It’s time to meet your partner!<br> class MyTest {</p> <p>private $a;</p> <p>public function getA() {</p> <p>return $this->a;</p> <p>}</p> <p>public function setA($a) {</p> <p> $this->a = $a;</p> <p>}</p> <p>}</p> <p>$useage = new MyTest();</p> <p>$useage->setA("HI~");</p> <p>echo $useage->getA();</p> <p>My own experience with JAVA</p> <p>Function has no return type<br> Use "->" instead of "."<br> to call methods and properties Regardless of whether it has been declared or not, always add $<br> in front of the variable. </p> <p>I don’t know what type the variable is... What should I do?<br> Cast </p> <p>(array)$sth</p> <p>Automatic conversion</p> <p>When calculating a string, take the previous number<br> The judgment condition of If() judges whether the calculation result is non-0<br> </p> <p>I want to have the right to know and control the variable type!<br> String Gettype( mixed var );<br> Return the type of variable var</p> <p>Boolean settype( mixed var , string type )<br> Convert the type of variable </p> <p> </p> <p>How big a part is the variable responsible for?<br> GLOBAL $var; //Global variable<br> STATIC $var; //Static variable<br> At present, only the keywords are different, the rest is normal</p> <p>Super global variables---predefined, related to the environment<br> $_SERVER , $_GET , $_POST , $_COOKIE</p> <p>$_FILES , $_ENV</p> <p> </p> <p>When the variable remains unchanged~<br> Define("PI" , 3.1415);</p> <p> </p> <p>Operator, operand, control statement<br> New:AND OR NOT XOR</p> <p>No others found yet...</p> <p><br> </p> <p>Excerpted from matter605924657</p> <p align="left"></p> <div style="display:none;"> <span id="url" itemprop="url">http://www.bkjia.com/PHPjc/478244.html</span><span id="indexUrl" itemprop="indexUrl">www.bkjia.com</span><span id="isOriginal" itemprop="isOriginal">true</span><span id="isBasedOnUrl" itemprop="isBasedOnUrl">http: //www.bkjia.com/PHPjc/478244.html</span><span id="genre" itemprop="genre">TechArticle</span><span id="description" itemprop="description">Finally the environment is configured, try PHP! Where should I write the code? ?php code ? ? code ? % code % script language=php code /script? Mark the author and comment? //author : matter /* *au...</span> </div> <div class="art_confoot"></div>
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