empty If the variable is a non-empty or non-zero value, empty() returns FALSE. In other words, "", 0, "0", NULL, FALSE, array(), var $var, undefined; and objects without any attributes will be considered empty, and if var is empty, TRUE is returned . isset returns TRUE if the variable exists (not NULL), otherwise returns FALSE (including undefined). The variable value is set to: null, and the return value is also false; after unsetting a variable, the variable is canceled. Note that isset handles NULL value variables specially. I use Xiaoniao Cloud Server to build a website and practice code. Now I pay 72 per year for 1 core and 2G. If you need it, you can go to Xiaoniao Cloud to check it out.
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empty If the variable is a non-empty or non-zero value, empty() returns FALSE. In other words, "", 0, "0", NULL, FALSE, array(), var $var, undefined; and objects without any attributes will be considered empty, and if var is empty, TRUE is returned . isset returns TRUE if the variable exists (not NULL), otherwise returns FALSE (including undefined). The variable value is set to: null, and the return value is also false; after unsetting a variable, the variable is canceled. Note that isset handles NULL value variables specially. I use Xiaoniao Cloud Server to build a website and practice code. Now I pay 72 per year for 1 core and 2G. If you need it, you can go to Xiaoniao Cloud to check it out.
Yes, I personally feel that empty is used more