新浪微博字数统计 textarea字数统计实现代码

/* 
* 从新浪微博上抄的 
* */ 
var getLength = (function(){ 
var trim = function(h) { 
try { 
return h.replace(/^\s+|\s+$/g, "") 
} catch(j) { 
return h 
} 
} 
var byteLength = function(b) { 
if (typeof b == "undefined") { 
return 0 
} 
var a = b.match(/[^\x00-\x80]/g); 
return (b.length + (!a ? 0 : a.length)) 
}; return function(q, g) { 
g = g || {}; 
g.max = g.max || 140; 
g.min = g.min || 41; 
g.surl = g.surl || 20; 
var p = trim(q).length; 
if (p > 0) { 
var j = g.min, 
s = g.max, 
b = g.surl, 
n = q; 
var r = q.match(/(http|https):\/\/[a-zA-Z0-9]+(\.[a-zA-Z0-9]+)+([-A-Z0-9a-z\$\.\+\!\_\*\(\)\/\,\:;@&=\?~#%]*)*/gi) || []; 
var h = 0; 
for (var m = 0, 
p = r.length; m < p; m++) { 
var o = byteLength(r[m]); 
if (/^(http:\/\/t.cn)/.test(r[m])) { 
continue 
} else { 
if (/^(http:\/\/)+(weibo.com|weibo.cn)/.test(r[m])) { 
h += o <= j ? o: (o <= s ? b: (o - s + b)) 
} else { 
h += o <= s ? b: (o - s + b) 
} 
} 
n = n.replace(r[m], "") 
} 
return Math.ceil((h + byteLength(n)) / 2) 
} else { 
return 0 
} 
} 
})();