php取得字符串首字母的方法

本文实例讲述了php取得字符串首字母的方法。分享给大家供大家参考。具体实现方法如下：

<?php$limit = array( //gb2312 拼音排序  array(45217,45252), //A  array(45253,45760), //B  array(45761,46317), //C  array(46318,46825), //D  array(46826,47009), //E  array(47010,47296), //F  array(47297,47613), //G  array(47614,48118), //H  array(0,0),     //I  array(48119,49061), //J  array(49062,49323), //K  array(49324,49895), //L  array(49896,50370), //M  array(50371,50613), //N  array(50614,50621), //O  array(50622,50905), //P  array(50906,51386), //Q  array(51387,51445), //R  array(51446,52217), //S  array(52218,52697), //T  array(0,0),     //U  array(0,0),     //V  array(52698,52979), //W  array(52980,53688), //X  array(53689,54480), //Y  array(54481,55289), //Z);$str="A:这是一个测试程序1";$str= iconv("UTF-8","gb2312", $str);echo $str."</br>";$i=0;while($i<strlen($str) ) {  $tmp=bin2hex(substr($str,$i,1));  if($tmp>='B0'){ //汉字的开始    $t=getLetter(hexdec(bin2hex(substr($str,$i,2))));    printf("%c",$t==-1 ? '*' : $t );    $i+=2;  }  else{    printf("%s",substr($str,$i,1));    $i++;  }}function getLetter($num){  global $limit;  $char_index=65;  foreach($limit as $k=>$v){    if($num>=$v[0] && $num<=$v[1]){      $char_index+=$k;      return $char_index;    }  }  return -1;}?>

希望本文所述对大家的php程序设计有所帮助。