JS validation control input in English byte length (input, textarea, etc.) specific examples _javascript skills

Check to see if the form meets the specified length. The maximum allowable n characters (2 digits in Chinese)!

Copy Code code as follows:

function Fucchecklength (strtemp) {
var i,sum;
sum=0;
for (i=0;i<strtemp.length;i++) {
if ((Strtemp.charcodeat (i) >=0) && (Strtemp.charcodeat (i) <=255)) {
sum=sum+1;
}else {
sum=sum+2;
}
}
return sum;
}

Use:

Copy Code code as follows:

M=fucchecklength (strtemp);
if (m>10) {
Alert ("Length is greater than 10 characters!") ");
}