Check text number in Textarea field

function textCounter(field, countfield, maxlimit) {
if (field.value.length >= maxlimit) {
alert("Over your writting.");
if (field.value.length > maxlimit ) {
field.value = field.value.substring(0, maxlimit-1)   
}  
} else {
if (field.value.length > maxlimit)
field.value = field.value.substring(0, maxlimit);
else
countfield.value = maxlimit - field.value.length;
}
}