删除特殊字符和限定用户输入长度的示例代码

<br>/检查非法字符并检验字符长度 <br>function checkSpeChar(obj, byteLength, title) { <br>var value = document.getElementById(obj).value; <br>value = value.replace(/(^\s*)/g, "").replace(/(\s*$)/g, ""); <br>var ret = (/[-|;|,|\/|\(|\)|\[|\]|\}|\{|%|@|\*|!|\']/.test(value)); <br>var arr = ["@", "#", "$", "%", "^", "&", "*", "<", ">", "/", "\\", "\'", "'", ".", ":", "?", "[", "]", ";", "-", "、", "(", ")", "_", "\"", "~", "insert", "delete", "update", "select"]; <br>value = value.toLowerCase(); <br>for (var i = 0; i < arr.length; i++) { <br>if (value.indexOf(arr[i].toLowerCase()) >= 0) { <br>ret = true; <br>} <br>} <br>if (ret == true) { <br>top.LSAlert("内容中含非法字符，请重新输入！"); <br>document.getElementById(obj).value = ''; <br>return; <br>} <br>limitLength(value, byteLength, title, obj); <br>} <br>//验证输入字符长度 <br>function limitLength(value, byteLength, title, attribute) { <br>value = value.replace(/\r/g, " ").replace(/\n/g, " "); //回车换行分别替换两个空格 <br>var newvalue = value.replace(/[^\x00-\xff]/g, "***"); <br>var length = newvalue.length; <br>//当填写的字节数小于设置的字节数 <br>if (length * 1 <= byteLength * 1) { <br>return; <br>} <br>var limitDate = newvalue.substr(0, byteLength); <br>var count = 0; <br>var limitvalue = ""; <br>for (var i = 0; i < limitDate.length; i++) { <br>var flat = limitDate.substr(i, 1); <br>if (flat == "*") { <br>count++; <br>} <br>} <br>var size = 0; <br>var istar = newvalue.substr(byteLength * 1 - 1, 1); //校验点是否为“×” <br>//if 基点是×; <br>if (count % 3 == 0) { <br>size = count / 3 + (byteLength * 1 - count); <br>limitvalue = value.substr(0, size); <br>} <br>else if (count % 3 == 1) { <br>size = (count - 1) / 3 + (byteLength * 1 - count); <br>limitvalue = value.substr(0, size); <br>} <br>else if (count % 3 == 2) { <br>size = (count - 2) / 3 + (byteLength * 1 - count); <br>limitvalue = value.substr(0, size); <br>} <br>//top.LSAlert(title + "最大输入" + byteLength + "个字节！"); <br>document.getElementById(attribute).value = limitvalue; <br>return; <br>} <br>