删除特殊字符和限定用户输入长度的示例代码

复制代码 代码如下:

  /检查非法字符并检验字符长度

  function checkSpeChar(obj, byteLength, title) {

  var value = document.getElementById(obj).value;

  value = value.replace(/(^\s*)/g, "").replace(/(\s*$)/g, "");

  var ret = (/[-|;|,|\/|\(|\)|\[|\]|\}|\{|%|@|\*|!|\']/.test(value));

  var arr = ["@", "#", "$", "%", "^", "&", "*", "<", ">", "/", "\\", "\'", "'", ".", ":", "?", "[", "]", ";", "-", "、", "(", ")", "_", "\"", "~", "insert", "delete", "update", "select"];

  value = value.toLowerCase();

  for (var i = 0; i < arr.length; i++) {

  if (value.indexOf(arr[i].toLowerCase()) >= 0) {

  ret = true;

  }

  }

  if (ret == true) {

  top.LSAlert("内容中含非法字符,请重新输入!");

  document.getElementById(obj).value = '';

  return;

  }

  limitLength(value, byteLength, title, obj);

  }

  //验证输入字符长度

  function limitLength(value, byteLength, title, attribute) {

  value = value.replace(/\r/g, " ").replace(/\n/g, " "); //回车换行分别替换两个空格

  var newvalue = value.replace(/[^\x00-\xff]/g, "***");

  var length = newvalue.length;

  //当填写的字节数小于设置的字节数

  if (length * 1 <= byteLength * 1) {

  return;

  }

  var limitDate = newvalue.substr(0, byteLength);

  var count = 0;

  var limitvalue = "";

  for (var i = 0; i < limitDate.length; i++) {

  var flat = limitDate.substr(i, 1);

  if (flat == "*") {

  count++;

  }

  }

  var size = 0;

  var istar = newvalue.substr(byteLength * 1 - 1, 1); //校验点是否为“×”

  //if 基点是×;

  if (count % 3 == 0) {

  size = count / 3 + (byteLength * 1 - count);

  limitvalue = value.substr(0, size);

  }

  else if (count % 3 == 1) {

  size = (count - 1) / 3 + (byteLength * 1 - count);

  limitvalue = value.substr(0, size);

  }

  else if (count % 3 == 2) {

  size = (count - 2) / 3 + (byteLength * 1 - count);

  limitvalue = value.substr(0, size);

  }

  //top.LSAlert(title + "最大输入" + byteLength + "个字节!");

  document.getElementById(attribute).value = limitvalue;

  return;

  }