


PHP data type conversion (character to number, number to character)
This article mainly introduces PHP data type conversion (character to number, number to character), which has a certain reference value. Now I share it with you. Friends in need can refer to it
PHP data Type conversion is a forced conversion. The PHP data types that are allowed to be converted are:
● (int), (integer): converted to integer
● (float), (double), (real) : Convert to floating point type
● (string): Convert to string
● (bool), (boolean): Convert to Boolean type
● (array) : Convert to array
● (object): Convert to object
There are three conversion methods for PHP data types:
● Add parentheses before the variable to be converted. The target type is
● Use three specific types of conversion functions, intval(), floatval(), strval() [Memory: the target type val() you want to convert]
● Use the general type conversion function settype(mixed var,string type)
The first conversion method: (int) (bool) (float) (string) ( array) (object)
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<?php $num1=3.14; $num2=(int)$num1; var_dump($num1); //输出float(3.14) var_dump($num2); //输出int(3) ?>
Second conversion method: intval() floatval() strval()
<?php $str="123.9abc"; $int=intval($str); //转换后数值:123 $float=floatval($str); //转换后数值:123.9 $str=strval($float); //转换后字符串:"123.9" ?>
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The third conversion method: settype();
<?php $num4=12.8; $flg=settype($num4,"int"); var_dump($flg); //输出bool(true) var_dump($num4); //输出int(12) ?>
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