jscript_textarea_counter.js

来自「Zen Cart是真正的电子商务艺术」· JavaScript 代码 · 共 15 行

/* javascript function to update form field
 *  field		form field that is being counted
 *  count		form field that will show characters left
 *  maxchars 	maximum number of characters
*/
function characterCount(field, count, maxchars) {
  var realchars = field.value.replace(/\t|\r|\n|\r\n/g,'');
  var excesschars = realchars.length - maxchars;
  if (excesschars > 0) {
		field.value = field.value.substring(0, excesschars);
		alert("Error:\n\n- You are only allowed to enter up to"+maxchars+" characters.");
	} else {
		count.value = maxchars - realchars.length;
	}
}