Regular Expression for determining numbers, letters, and Chinese characters in js (example)

/*
Determines whether the specified content is null. If it is null, a warning box is displayed.
*/
Function isEmpty (theValue, strMsg ){
If (theValue = ""){
Alert (strMsg + "cannot be blank! ");
Return true;
}
Return false;
}
/*
Chinese judgment function, which allows the replacement of uncommon words with English "*"
True indicates that the condition is met, and false indicates that the condition is not met.
*/
Function isChinese (str ){
Var badChar = "ABCDEFGHIJKLMNOPQRSTUVWXYZ ";
BadChar + = "abcdefghijklmnopqrstuvwxyz ";
BadChar + = "0123456789 ";
BadChar + = "" + ""; // halfwidth and fullwidth Spaces
BadChar + = "www.jb51.net does not contain English characters * or.
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I); // character in string str
If (badChar. indexOf (c)>-1 ){
Return false;
}
}
Return true;
}
/*
Number judgment function. If true is returned, all digits are returned. If false is returned, not all digits are returned.
*/
Function isNumber (str ){
If ("" = str ){
Return false;
}
Var reg =/\ D /;
Return str. match (reg) = null;
}
/*
Determines whether the given string is a number of the specified length.
True is returned, not false.
*/
Function isNumber_Ex (str, len ){
If ("" = str ){
Return false;
}
If (str. length! = Len ){
Return false;
}
If (! IsNumber (str )){
Return false;
}
Return true;
}
/*
The money judgment function allows the first digit to be "-" to indicate that the account is in arrears.
True indicates that the format is correct. false indicates that the format is incorrect.
*/
Function isMoney (str ){
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I );
If (I = 0 ){
If (c! = "-" & (C <"0" | c> "9 ")){
Return false;
} Else if (c = "-" & str. length = 1 ){
Return false;
}
} Else if (c <"0" | c> "9 "){
Return false;
}
}
Return true;
}
/*
Returns true to indicate all English letters, and false to indicate not all English letters.
*/
Function isLetter (str ){
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I );
If (c <"a" | c> "z") & (c <"A" | c> "Z ")){
Return false;
}
}
Return true;
}
/*
Space determines. If a space is included, false is returned. If a space is not included, true is returned.
"" Cannot be judged
*/
Function notInSpace (str ){
If ("" = str ){
Return false;
}
Var badChar = "";
BadChar + = "";
For (var I = 0; I var c = str. charAt (I); // character in string str
If (badChar. indexOf (c)>-1 ){
Return false;
}
}
Return true;
}
/*
** Number judgment function. If the return value is true, the return value is **. If the return value is false, the return value is invalid.
*/
Function isFPH (str ){
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I );
If (c <"0" | c> "9") & (c! = "-") & (C! = ",")){
Return false;
}
}
Return true;
}
/*
Telephone judgment function, which allows "Number", ";", "-", "(", ")",
True indicates the phone number.
*/
Function isTelephone (str ){
Var trueChar = "()-; 1234567890 ";
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I); // character in string str
If (trueChar. indexOf (c) =-1) return false;
}
Return true;
}
/**
The length can be 1-7, or 3.5, and cannot exceed 7 or less than 1 year.
*/
Function isXZ (str ){
If ("" = str ){
Return false;
}
Var reg =/^ [1-6] (\. 5 )? $ /;
Var r = str. match (reg );
If (null! = R ){
Return true;
} Else {
If (str = "7 "){
Return true;
} Else {
Return false;
}
}
}
/*
Determine whether the certificate number meets the requirements. The certificate number contains Chinese characters, numbers, uppercase/lowercase letters, (,), and ,(,),-
True is returned, not false.
*/
Function isZSBH (str ){
If ("" = str ){
Return false;
}
For (var I = 0; I var c = str. charAt (I );
Alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ ";
Alpha + = "abcdefghijklmnopqrstuvwxyz ";
Alpha + = "()-";
If (! IsChinese (c )&&! IsNumber (c) & alpha. indexOf (c) =-1 ){
Return false;
}
}
Return true;
}
/*
ID card judgment function. true is returned, not false.
15 digits, 18 digits or the last digit is X (uppercase)
*/
Function isSFZ (str ){
If ("" = str ){
Return false;
}
If (str. length! = 15 & str. length! = 18) {// incorrect ID card Length
Return false;
}
If (str. length = 15 ){
If (! IsNumber (str )){
Return false;
}
} Else {
Str1 = str. substring (0, 17 );
Str2 = str. substring (17,18 );
Alpha = "X0123456789 ";
If (! IsNumber (str1) | alpha. indexOf (str2) =-1 ){
Return false;
}
}
Return true;
}
/*
Get the year, month, and day of today
Call method: today = new getToday (); then today. year is the year of today, and so on.
*/
Function getToday (){
This. now = new Date ();
This. year = this. now. getFullYear ();
This. month = this. now. getMonth ();
This. day = this. now. getDate ();
}

Js determines numbers, letters, and Chinese characters
1.
Var reg =/^ (\ w | [\ u4E00-\ u9FA5]) * $ /;
If (arr = username. match (reg ))
{
Ti = 1;
Return ture;
}
Else
{
Alert ("the user name can only contain English letters, numbers and Chinese characters. \ n check whether there are spaces or other symbols before and after ");
Ti = 0;
Return false;
}
2. Use regular expressions to restrict text box input in a webpage form:
You can only enter Chinese characters using regular expressions: onkeyup = "value = value. replace (/[^ \ u4E00-\ u9FA5]/g, '')" onbeforepaste = "clipboardData. setData ('text', clipboardData. getData ('text '). replace (/[^ \ u4E00-\ u9FA5]/g ,''))"
You can only enter the full-width characters: onkeyup = "value = value. replace (/[^ \ uFF00-\ uFFFF]/g, '')" onbeforepaste = "clipboardData. setData ('text', clipboardData. getData ('text '). replace (/[^ \ uFF00-\ uFFFF]/g ,''))"
Use a regular expression to limit that only numbers can be entered: onkeyup = "value = value. replace (/[^ \ d]/g, '')" onbeforepaste = "clipboardData. setData ('text', clipboardData. getData ('text '). replace (/[^ \ d]/g ,''))"
You can only enter numbers and English letters using regular expressions: onkeyup = "value = value. replace (/[\ W]/g, '')" onbeforepaste = "clipboardData. setData ('text', clipboardData. getData ('text '). replace (/[^ \ d]/g ,''))"

Number
<Script>
Function check ()
{
If (! IsNaN (document. all. form. str. value ))
{
Alert ("Number ");
}
</Script>
Letter
<Script>
Function check ()
{
Var str =/[_ a-zA-Z]/;
If (str. test (document. all. form. str. value ))
{
Alert ("letter ");
}
}
</Script>
<Form name = "form" action = "" onsubmit = "return check ();">
<Input type = text name = str>
<Input type = submit>
<Form>
---------------------------------------------------
/**
* Some Common javascript Functions (methods)
*
* For ease of use, all methods written as String objects
* Save it as a. js file to conveniently extend the function of a string object.
*
* Method name
*-------------------------------------------
* Trim deletes the first space.
* Occurs counts the number of times a specified character appears
* IsDigit checks whether it is composed of digits
* IsAlpha checks whether the data is composed of digits, letters, and underscores.
* Check the number of isnumbers
* Lenb returns the number of bytes.
* IsInChinese check for Chinese Characters
* Simple isEmail email check
* IsDate: A simple date check. A date object is returned successfully.
* IsInList check whether there are character characters in the list
* IsInList check whether there are character characters in the list
*/
/*** Delete spaces at the beginning and end ***/
String. prototype. Trim = function (){
Return this. replace (/(^ \ s *) | (\ s * $)/g ,"");
}
/*** Count the number of times a specified character appears ***/
String. prototype. Occurs = function (ch ){
// Var re = eval ("/[^" + ch + "]/g ");
// Return this. replace (re, ""). length;
Return this. split (ch). length-1;
}
/*** Check whether the data is composed of digits ***/
String. prototype. isDigit = function (){
Var s = this. Trim ();
Return (s. replace (/\ d/g, ""). length = 0 );
}
/*** Check whether it is composed of digits, letters, and underscores ***/
String. prototype. isAlpha = function (){
Return (this. replace (/\ w/g, ""). length = 0 );
}
/*** Check the number of items ***/
String. prototype. isNumber = function (){
Var s = this. Trim ();
Return (s. search (/^ [+-]? [0-9.] * $/)> = 0 );
}
/*** Number of returned bytes ***/
String. prototype. lenb = function (){
Return this. replace (/[^ \ x00-\ xff]/g, "**"). length;
}
/*** Check whether Chinese characters are contained ***/
String. prototype. isInChinese = function (){
Return (this. length! = This. replace (/[^ \ x00-\ xff]/g, "**"). length );
}
/*** Simple email check ***/
String. prototype. isEmail = function (){
Var strr;
Var mail = this;
Var re =/(\ w + @ \ w + \. \ w + )(\. {0, 1} \ w *)(\. {0, 1} \ w *)/I;
Re.exe c (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;
Return (strr = mail );
}
/*** Simple date check. The date object is returned successfully ***/
String. prototype. isDate = function (){
Var p;
Var re1 =/(\ d {4}) [year. /-] (\ d {1, 2}) [month. /-] (\ d {1, 2}) [Day]? $ /;
Var re2 =/(\ d {1, 2}) [month. /-] (\ d {1, 2}) [Day. /-] (\ d {2}) [year]? $ /;
Var re3 =/(\ d {1, 2}) [month. /-] (\ d {1, 2}) [Day. /-] (\ d {4}) [year]? $ /;
If (re1.test (this )){
P = re1.exec (this );
Return new Date (p [1], p [2], p [3]);
}
If (re2.test (this )){
P = re2.exec (this );
Return new Date (p [3], p [1], p [2]);
}
If (re3.test (this )){
P = re3.exec (this );
Return new Date (p [3], p [1], p [2]);
}
Return false;
}
/*** Check whether there are any character characters in the list ***/
String. prototype. isInList = function (list ){
Var re = eval ("/[" + list + "]/");
Return re. test (this );
}