JS numbers, Chinese characters, English letters, judgment

Separate Verification:
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 ,''))"
Non-regular expression: (restrict the input of special characters)
<Input type = "text" name = "name" onkeydown = checkKey1 () onkeypress = checkKey2 ()>
Function checkKey1 (){
If (event. keyCode = 13 ){
User_login ();
} Else if (! (Event. keyCode> = 48) & (event. keyCode <= 57) | (event. keyCode> = 65) & (event. keyCode <= 90) | (event. keyCode> = 97) & (event. keyCode <= 122) | (event. keyCode> = 37) & (event. keyCode <= 40) | (event. keyCode = 95) | (event. keyCode = | (event. keyCode = 189) | (event. keyCode = 46) | (event. keyCode = 9 ))){
Event. returnValue = false;
}
}
Function checkKey2 (){
If (! (Event. keyCode> = 48) & (event. keyCode <= 57) | (event. keyCode> = 65) & (event. keyCode <= 90) | (event. keyCode> = 97) & (event. keyCode <= 122) | (event. keyCode = 95) | (event. keyCode = | (event. keyCode = 189) | (event. keyCode = 46 ))){
Event. returnValue = false;
}
}

Only Chinese characters, English letters, and numbers are allowed:
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>

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/^ [0-9a-zA-Z] + $/

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/**
* 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 );
}