动态显示可输入的字数提示还可以输入的字数_javascript技巧

还可以输入15字数

function setShowLength(obj, maxlength, id)
{
var rem = maxlength - obj.value.length;
var wid = id;
if (rem < 0){
rem = 0;
}
document.getElementById(wid).innerHTML = "还可以输入" + rem + "字数";
}