PHP - 用名为string的变量替换字符串

Question

所以字符串是这样的:

"bla bla bla {VARIABLE} bla bla"

当我在函数中的某个地方使用这个字符串时,我想用$ variable(或任何其他包含在{} charcters中的大写字符串)替换{VARIABLE}.$ variable(和任何其他变量)将在该函数内定义

我能这样做吗？

Answer 1

$TEST = 'one';
$THING = 'two';
$str = "this is {TEST} a {THING} to test";

$result = preg_replace('/\{([A-Z]+)\}/e', "$$1", $str);

Answer 2

使用正则表达式查找所有替换,然后迭代结果并替换它们.请务必仅允许您想要公开的变量.

// white list of variables
$allowed_variables = array("test", "variable", "not_POST", "not_GET",); 

preg_match("#(\{([A-Z]+?)\}#", $text, $matches);

// not sure the result is in [1], do a var_dump
while($matches[1] as $variable) { 
    $variable = strtolower($variable);

    // only allow white listed variables
    if(!in_array($variable, $allowed_variables)) continue; 

    $text = str_replace("{".$match."}", $$match, $text);
}