JS验证字符串功能

js 验证字符串功能实例代码如下所示：

//去除空格 
function jsTrim(value) { 
  var reg = /^\S$/; 
  if (!value) return ""; 
  if (value.length == 0) 
    return value; 
  else { 
    var lp, rp; 
    lp = 0; rp = value.length - 1; 
    while ((value.charAt(lp) == " " || (value.charCodeAt(lp) < 128 ? (reg.test(value.charAt(lp)) == false ? true : false) : false) || value.charAt(rp) == " " || (value.charCodeAt(rp) < 128 ? (reg.test(value.charAt(rp)) == false ? true : false) : false)) && rp >= lp) { 
      if (value.charAt(lp) == " " || value.charCodeAt(lp) < 128 ? (reg.test(value.charAt(lp)) == false ? true : false) : false) 
        lp++; 
      if (value.charAt(rp) == " " || value.charCodeAt(rp) < 128 ? (reg.test(value.charAt(rp)) == false ? true : false) : false) 
        rp--; 
    } 
    if (lp > rp) 
      return ""; 
    else 
      return (value.substring(lp, rp + 1)); 
  } 
} 
//字符串长度 
function strlength(s) { 
  var s_length = s.length; 
  return s_length; 
} 
//手机号码验证函数 
String.prototype.Trim = function() { 
  var m = this.match(/^\s*(\S+(\s+\S+)*)\s*$/); 
  return (m == null) ? "" : m[1]; 
} 
String.prototype.isMobile = function() { 
  return (/^(?:13\d|15\d|18\d|19\d|17\d|14\d)-?\d{5}(\d{3}|\*{3})$/.test(this.Trim())); 
} 
//*判别电话号码，手机号是否有效 
//*返回 true:false 
//*/ 
function checkPhone(phone)   
{   
//验证电话号码手机号码，包含153，159号段   
if (phone==""){   
alert("电话号码不能为空！");    
return false;   
}   
if (phone != ""){    
var p1 = /^(([0\+]\d{2,3}-)?(0\d{2,3})-)?(\d{7,8})(-(\d{3,}))?$/;   
var me = false;   
if (p1.test(phone)) me=true;   
if (!me){     
//alert('对不起，您输入的电话号码有错误。区号和电话号码之间请用-分割');    
return false;   
}   
}   
return true;   
}   
//邮箱地址验证函数 
function checkmail(mail) { 
//  var strr; 
//  re = /(\w+@\w+\.\w+)(\.{0,1}\w*)(\.{0,1}\w*)/i; 
//  re.exec(mail); 
//  if (RegExp.$3 != "" && RegExp.$3 != "." && RegExp.$2 != ".") 
//    strr = RegExp.$1 + RegExp.$2 + RegExp.$3 
//  else { 
//    if (RegExp.$2 != "" && RegExp.$2 != ".") 
//      strr = RegExp.$1 + RegExp.$2 
//    else 
//      strr = RegExp.$1 
//  } 
//  if (strr != mail) { return false } else { return true } 
  //  return true; 
  var remail = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/; 
  return mail.match(remail); 
} 
//判断数字 
function CheckNumber(n) { 
  var checkOK = "0123456789-."; 
  var allValid = true; 
  var decPoints = 0; 
  var allNum = ""; 
  for (i = 0; i < n.length; i++) { 
    ch = n.charAt(i); 
    for (j = 0; j < checkOK.length; j++) 
      if (ch == checkOK.charAt(j)) 
      break; 
    if (j == checkOK.length) { 
      allValid = false; 
      break; 
    } 
    if (ch == ".") { 
      allNum += "."; 
      decPoints++; 
    } 
    else 
      allNum += ch; 
  } 
  if (!allValid) 
    return false; 
  if (decPoints > 1) 
    return false; 
  return true; 
} 
//判断数字 
function CheckN(n) { 
  var checkOK = "0123456789"; 
  var allValid = true; 
  var decPoints = 0; 
  var allNum = ""; 
  for (i = 0; i < n.length; i++) { 
    ch = n.charAt(i); 
    for (j = 0; j < checkOK.length; j++) 
      if (ch == checkOK.charAt(j)) 
      break; 
    if (j == checkOK.length) { 
      allValid = false; 
      break; 
    } 
    if (ch == ".") { 
      allNum += "."; 
      decPoints++; 
    } 
    else 
      allNum += ch; 
  } 
  if (!allValid) 
    return false; 
  if (decPoints > 1) 
    return false; 
  return true; 
} 
var g_MINY = 1601; 
var g_MAXY = 4500; 
var rgMC = new Array(12); 
rgMC[0] = 31; rgMC[1] = 28; rgMC[2] = 31; rgMC[3] = 30; rgMC[4] = 31; rgMC[5] = 30; rgMC[6] = 31; rgMC[7] = 31; rgMC[8] = 30; rgMC[9] = 31; rgMC[10] = 30; rgMC[11] = 31; 
function isdigit(c) { 
  return (c >= '0' && c <= '9'); 
} 
function GetMonthCount(m, y) { 
  var c = rgMC[m - 1]; 
  if ((2 == m) && IsLeapYear(y)) c++; 
  return c; 
} 
function atoi(s) { 
  var t = 0; 
  for (var i = 0; i < s.length; i++) { 
    var c = s.charAt(i); 
    if (!isdigit(c)) return t; 
    else t = t * 10 + (c - '0'); 
  } 
  return t; 
} 
//判断日期 
function CheckDate(t) { 
  var l = t.length; 
  if (0 == l) return false; 
  var cSp = '\0'; 
  var sSp1 = ''; 
  var sSp2 = ''; 
  for (var i = 0; i < t.length; i++) { 
    var c = t.charAt(i); 
    if (c == ' ' || isdigit(c)) continue; 
    else if (cSp == '\0' && (c == '/' || c == '-' || c == '.')) { 
      cSp = c; 
      sSp1 = t.substring(i + 1, l); 
    } 
    else if (c == cSp) sSp2 = t.substring(i + 1, l); 
    else if (c != cSp) return false; 
  } 
  if (0 == sSp1.length) return false; 
  var m; 
  var d; 
  var y; 
  if (0 == sSp2.length) return false; 
  m = atoi(sSp1); 
  d = atoi(sSp2); 
  y = atoi(t); 
  if (y < 100) { 
    y = 1900 + y; 
    while (y < g_yLow) y = y + 100; 
  } 
  if (y < g_MINY || y > g_MAXY || m < 1 || m > 12) return false; 
  if (d < 1 || d > GetMonthCount(m, y)) return false; 
  g_month = m; 
  g_day = d; 
  g_year = y; 
  return true; 
} 
//验证字符串必须为数字字母组合 
function isNumAndStr(elem){ 
    var str = elem.value;  
   var regexpUperStr=/[A-Z]+/; 
   var reexpLowerStr=/[a-z]+/; 
   var regexpNum=/\d+/; 
   var uperStrFlag = regexpUperStr.test(str); 
   var lowerStrFlag = reexpLowerStr.test(str); 
   var numFlag = regexpNum.test(str); 
   if((uperStrFlag&&lowerStrFlag)||(lowerStrFlag&&numFlag)||(uperStrFlag&&numFlag)) 
     return true; 
   else 
    return false; 
} 
//验证字符串必须为数字跟字母的组合   
function checkPSW(str) { 
  if (str != "") { 
    var p1 = /(?!^[0-9]*$)(?!^[a-zA-Z]*$)^([a-zA-Z0-9]{2,})$/; 
    var me = false; 
    if (p1.test(str)) me = true; 
    if (!me) { 
      return false; 
    } 
  } 
  return true; 
} 
//验证字符串必须为数字跟字母的组合   
function checklen(str) { 
  if (str.length < 8 ) { 
      return false; 
    } 
  return true; 
} 
//单价 
function ISprice(v) { 
  var Mreg = /^[0-9]{1,10}(\.[0-9]{1,3})?$/; 
  if (Mreg.test(v)) { 
    return true; 
  } 
  else { 
    return false; 
  } 
}

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