php 大括号和字符串

Question

谁能向我解释如何在 php 字符串中使用大括号 { } ？就像

“这是一个{$variable}”
“这是一个 {$user -> getName($variable);} 名称”

Answer 1

如果遇到美元符号（$），解析器将贪婪地获取尽可能多的标记来形成有效的变量名称。将变量名称括在大括号中以显式指定名称的结尾。

<?php
$beer = 'Heineken';
echo "$beer's taste is great"; // works; "'" is an invalid character for variable names
echo "He drank some $beers";   // won't work; 's' is a valid character for variable names but the variable is "$beer"
echo "He drank some ${beer}s"; // works
echo "He drank some {$beer}s"; // works
?>

来源

Answer 2

它用于指定变量名的结尾，例如：

$var = "apple";

echo "I love $var!"; //I love apple!
echo "I love $vars!"; // I love !
echo "I love {$var}s!"; //I love apples!
echo "I love ${var}s!"; //I love apples! //same as above

Answer 3

此外，语法“this is a {$user -> getName($variable);} name”无效。您不能在字符串内调用函数/方法。但是你可以这样做：

"this is a " . $user->getName($varaible) . " name"