print: 3.13 PI 3.14
<?php// $3some is not a valid variable name// This will not work$3some = 'invalid';// This worksdefine('3some', 'valid');echo constant('3some');?>Of course this is not a good practice, but PHP has got you covered. up down 2 Anonymous ¶ 16 years ago In reply to ...
document.write("The value of const variable x = " + x); OutputThe value of const variable x = 16 PHPIn PHP, there are two ways of defining a constant variable that is by using the define() function or by using the const keyword. Constants are similar to the variable except that ...
<?php define('ONE', 100); define('TWO', 100); $res= ONE+TWO; print "Sum of two constant=".$res; ?> OutputSum of two constant = 200 In the above example We define two constant with name(one,two) and value(100,100) respectively. $res variable is also define. Now we perform ...
这个是你使用的时候，用的是include或者require吧 两次载入就会造成这问题，其实你只需要用require_once()一下就可以了，第二个问题是在使用变量的时候未定义
constant()is useful if you need to retrieve the value of a constant, but do not know its name. i.e. It is stored in a variable or returned by a function. 例子1.constant()example <?php define("MAXSIZE",100); echoMAXSIZE;
constant() is useful if you need to retrieve the value of a constant, but do not know its name. i.e. It is stored in a variable or returned by a function. 例子1. constant() example <?phpdefine("MAXSIZE", 100);echo MAXSIZE;echo constant("MAXSIZE"); // same thing as the previ...
keyword in front of the variable type. This will declare the variable as "constant", which means unchangeable and read-only:ExampleGet your own C# Server const int myNum = 15; myNum = 20; // error Try it Yourself » The const keyword is useful when you want a variable to always ...
Notice: Undefined variable: content in E:\Server\vhosts\www.lvtao.net\libs\template.core.php on line 557 进入网站会出现大量类似下面的提示,但是可以正常显示和运行 Notice: Use of undefined constant ctbTitle - assumed 'ctbTitle' in d:\ctb1.5\ctb\include\config.php on line 23... ...
求教php运行时出错:Parse error: syntax error, unexpected T_STRING, expecting T_FUNCTION 。。。 因为没有看到完整的代码,只能大致猜测一下: 出现:syntax error, unexpected T_STRI PHP的Parse error: syntax error, unexpected T_VARIABLE in 是什么意思? $a="/a/b/c/d/e.php"; $b="/a/b/12/34/...