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PHP如何使用全局变量

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Jun 23, 2016 pm 02:15 PM

PHP 全局变量

<?phpglobal $vfp_oledb_CString;$vfp_oledb_CString="Provider=VFPOLEDB.1;Data Source=d:/testoledb; Collating Sequence=MACHINE";testgol();function testgol(){echo $vfp_oledb_CString;}

结果是没有任何输出, 应该如何定义和使用全局变量呢

回复讨论(解决方案)

$vfp_oledb_CString="Provider=VFPOLEDB.1;Data Source=d:/testoledb; Collating Sequence=MACHINE";
testgol();

function testgol(){
global $vfp_oledb_CString;
echo $vfp_oledb_CString;
}

不建议使用global关键字，还是用$GLOBALS超全局变量吧

装个yac吧。进程间共享内存，很好用。

还需要在调用时再声明一次吗? .

这个字串是用来声明. vfp表的目录位置的, 我想把它作为一个配置文件用来include
然后在一个PHP 文件的各个 FUNCTION 中使用, 要达到这样的效果. 应该使用那种方法比较好

也可以用$GLOBAL超全局变量
$vfp_oledb_CString="Provider=VFPOLEDB.1;Data Source=d:/testoledb; Collating Sequence=MACHINE";
testgol();

function testgol(){
echo $GLOBALS['vfp_oledb_CString'];
}

如果你的字串是固定的，你可以把它定义成常量，常量的范围是全局的。不用管作用区域就可以在脚本的任何地方访问常量。

使用常量问题解决了.多谢费心.

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