PHP Data type, true or false? 1. are all resource types true? 2. are NULL types false? Share: PHP Data type, true or false?
1. are all resource types true?
2. are NULL types false? Share:
------ Solution --------------------
All null values are treated as "false": 0, '0', '', false, null, array ()....
Otherwise, it is regarded as "true"
------ Solution --------------------
When converted to boolean, the following values are considered FALSE:
Boolean value FALSE
Integer value 0 (0)
Floating point value: 0.0 (0)
Empty string and string "0"
Array that does not contain any elements
Objects that do not include any member variables (applicable only to PHP 4.0)
Special type NULL (including unassigned variables) SimpleXML object generated from an XML document without any tags
All other values are considered TRUE (
Including any resources).
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