function getLeftChars(varField,limit_len) {
var i = 0;
var counter = 0;
var cap = limit_len;
var j=0;
for (i = 0; i< varField.value.length; i++) {
if (varField.value.charCodeAt(i) > 127 || varField.value.charCodeAt(i) == 94) {
j=j+2;
}
else {
j=j+1
}
} //结束FOR循环
//var leftchars = cap - varField.value.length;
var leftchars = cap - j;
return (leftchars);
}