# IntlChar::isalnum

(PHP 7, PHP 8)

IntlChar::isalnum — Check if code point is an alphanumeric character

### 说明

public static IntlChar::isalnum(int|string `$codepoint`): ?bool

Determines whether the specified code point is an alphanumeric character (letter or digit). `true` for characters with general categories "L" (letters) and "Nd" (decimal digit numbers).

### 参数

`codepoint`

  The int codepoint value (e.g. `0x2603` for U+2603 SNOWMAN), or the character encoded as a UTF-8 string (e.g. `"\u{2603}"`)

### 返回值

Returns `true` if `codepoint` is an alphanumeric character, `false` if not. Returns `null` on failure.

### 示例

示例 #1 Testing different code points

`<?php
var_dump(IntlChar::isalnum("A"));
var_dump(IntlChar::isalnum("1"));
var_dump(IntlChar::isalnum("\u{2603}"));
?>`

以上示例会输出：

    bool(true)
    bool(true)
    bool(false)

### 参见

- IntlChar::isalpha() - Check if code point is a letter character
- IntlChar::isdigit() - Check if code point is a digit character
- ctype_alnum() - 检测字母数字式字符

`↑` and `↓` to navigate • `Enter` to select • `Esc` to close • `/` to open