Int和str变量

Question

我对php中的整数和字符串变量的规则有点不清楚。

如果我正在处理计数器（从1开始并向上计数的简单整数），我是否需要将变量指定为整数然后在我使用时转换为字符串，或者我可以将它们保留为字符串并且转换将自动发生在php中在运行时间？

或者是否存在太多具有不同规则的特定案例？一些想法将不胜感激......

Answer 1

PHP中没有变量声明，变量将采用适合您分配给它的数据的类型。

$var = 1;    //here $var is an int
$var = '1';  // now is a string
$var = true; //and now a boolean

Answer 2

PHP会在需要时自动转换valriables。当你要比较它们时，你必须要小心。

If you compare a number with a string or the comparison involves numerical strings, then each string is converted to a number and the comparison performed numerically. These rules also apply to the switch statement. The type conversion does not take place when the comparison is === or !== as this involves comparing the type as well as the value.

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