①单引号内部的变量不会执行， 双引号会执行
②单引号解析速度比双引号快。
③单引号只能解析部分特殊字符，双引号可以解析所有特殊字符。
php中单引号双引号的区别？
微信公众号
手机浏览(小程序)
Warning: get_headers(): SSL operation failed with code 1. OpenSSL Error messages: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed in /mydata/web/wwwshanhubei/web/wp-content/themes/shanhuke/single.php on line 57
Warning: get_headers(): Failed to enable crypto in /mydata/web/wwwshanhubei/web/wp-content/themes/shanhuke/single.php on line 57
Warning: get_headers(https://static.shanhubei.com/qrcode/qrcode_viewid_55175.jpg): failed to open stream: operation failed in /mydata/web/wwwshanhubei/web/wp-content/themes/shanhuke/single.php on line 57
