The boolval function is used to get the Boolean value of a variable.
Version requirements: PHP 5 >= 5.5.0, PHP 7.
grammar
boolean boolval (mixed $var)
Parameter description:
$var: The variable to be converted to a boolean value.
Example
Example
<?php echo ' 0: ' . ( boolval ( 0 ) ? ' true ' : ' false ' ) . " n " ; echo ' 42: ' . ( boolval ( 42 ) ? ' true ' : ' false ' ) . " n " ; echo ' 0.0: ' . ( boolval ( 0 .0 ) ? ' true ' : ' false ' ) . " n " ; echo ' 4.2: ' . ( boolval ( 4 .2 ) ? ' true ' : ' false ' ) . " n " ; echo ' "": ' . ( boolval ( " " ) ? ' true ' : ' false ' ) . " n " ; echo ' "string": ' . ( boolval ( " string " ) ? ' true ' : ' false ' ) . " n " ; echo ' "0": ' . ( boolval ( " 0 " ) ? ' true ' : ' false ' ) . " n " ; echo ' "1": ' . ( boolval ( " 1 " ) ? ' true ' : ' false ' ) . " n " ; echo ' [1, 2]: ' . ( boolval ( [ 1 , 2 ] ) ? ' true ' : ' false ' ) . " n " ; echo ' []: ' . ( boolval ( [ ] ) ? ' true ' : ' false ' ) . " n " ; echo ' stdClass: ' . ( boolval ( new stdClass ) ? ' true ' : ' false ' ) . " n " ; ?> The execution result is as follows:
0: false42: true0.0: false4.2: true"": false"string": true"0": false"1": true[1, 2]: true[]: falsestdClass: true
