IntlChar::isIDStart
(PHP 7)
IntlChar::isIDStart — Check if code point is permissible as the first character in an identifier
说明
Determines if the specified character is permissible as the first character in an identifier according to Unicode (The Unicode Standard, Version 3.0, chapter 5.16 Identifiers).
TRUE
for characters with general categories "L" (letters) and "Nl" (letter numbers).
参数
返回值
Returns TRUE
if
codepoint
may start an identifier, FALSE
if not.
范例
Example #1 Testing different code points
<?php
var_dump(IntlChar::isIDStart("A"));
var_dump(IntlChar::isIDStart("$"));
var_dump(IntlChar::isIDStart("\n"));
var_dump(IntlChar::isIDStart("\u{2603}"));
?>
以上例程会输出:
bool(true) bool(false) bool(false) bool(false)
参见
- IntlChar::isalpha() - Check if code point is a letter character
- IntlChar::isIDPart() - Check if code point is permissible in an identifier
IntlChar::PROPERTY_ID_START