PHP中的ctype_alpha()函数
ctype_alpha()函数检查字母字符。如果文本中的每个字符都是字母，则返回TRUE，否则返回FALSE。
语法
ctype_alpha ( $str );
参数
str-测试的字符串
返回
如果文本中的每个字符都是字母，则ctype_alpha()函数返回TRUE，否则返回FALSE。
示例
以下是一个例子-
<?php
$str = array('demo', 'de967demo');
foreach ($str as $a) {
if (ctype_alpha($a)) {
echo "$a consists of all letters. \n";
} else {
echo "$a does not have all letters. \n";
}
}
?>输出结果
以下是输出-
demo consists of all letters. de967demo does not have all letters.