统计字符串中的大小写字母个数

<textarea cols="20" rows="10" id="dome1"></textarea><h2 id="dome2">剩余(100)个字符</h2><br /><button οnclick="func1()">统计个数</button><div id="dome"></div>

js：操作

function func1(){var x = document.getElementById("dome1").value;var upCount = 0;var lowCount = 0;var otherCount = 0;for (var i=0;i<x.length;i++) {var c = x.charAt(i);if (c >= 'a' && c <='z') {lowCount++;} else if(c >= 'A' && c <='Z'){upCount++;}else{otherCount++;}}var zifu =Number(x.length);var da = 120 - zifu;document.getElementById("dome2").innerHTML="剩余("+da+")个字符";document.getElementById("dome").innerHTML="大写字母个数为:"+upCount+",小写字母个数为"+lowCount+",其他字符:"+otherCount;}