Regular-expression validation

/determine if the input content is empty
function IsNull () {
var str = document.getElementById (' str '). Value.trim ();
if (str.length==0) {
Alert (' Sorry, the text box cannot be empty or blank! '); /Please change the text box to the name of the property you need to verify!
}
}

Determine whether the date type is a type of YYYY-MM-DD format
function IsDate () {
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
var reg =/^ (\d{1,4}) (-|\/) (\d{1,2}) \2 (\d{1,2}) $/;
var r = Str.match (reg);
if (r==null)
Alert (' Sorry, the date you entered is not in the correct format! '); Please change "date" to the name of the property you need to verify!
}
}

Type that determines whether the date type is YYYY-MM-DD hh:mm:ss format
function Isdatetime () {
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
var reg =/^ (\d{1,4}) (-|\/) (\d{1,2}) \2 (\d{1,2}) (\d{1,2}):(\d{1,2}):(\d{1,2}) $/;
var r = Str.match (reg);
if (r==null)
Alert (' Sorry, the date you entered is not in the correct format! '); Please change "date" to the name of the property you need to verify!
}
}

Determine whether the date type is a type of HH:MM:SS format
function Istime ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^ ((20|21|22|23|[ 0-1]\d) \:[0-5][0-9]) (\:[0-5][0-9])? $/
if (!reg.test (str)) {
Alert ("Sorry, the date you entered is not in the correct format!"); /Please change the "date" to the name of the property you need to verify!
}
}
}

Determine if the character entered is an English letter
function Isletter ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^[a-za-z]+$/;
if (!reg.test (str)) {
Alert ("Sorry, the English letter type you typed is not properly formatted!"); /Please change the "English letter type" to the name of the property you need to verify!
}
}
}

Determines whether the input character is an integer
function Isinteger ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^[-+]?\d*$/;
if (!reg.test (str)) {
Alert ("Sorry, the integer type you entered is not formatted correctly!"); /Please replace the "integer type" with the name of the property you want to verify!
}
}
}

Determines whether the input character is double precision
Function Isdouble (val)
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
Reg=/^[-\+]?\d+ (\.\d+) $/;
if (!reg.test (str)) {
Alert ("Sorry, the double type you entered is not in the correct format!"); /Please replace "double type" with the name of the property you want to verify!
}
}
}


Determine if the character entered is: a-z,a-z,0-9
function isstring ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^[a-za-z0-9_]+$/;
if (!reg.test (str)) {
Alert ("Sorry, you typed the string type incorrectly!"); /Please replace "string type" with the name of the property you want to verify!
}
}
}

Determines whether the character entered is in Chinese
function Ischinese ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^[\u0391-\uffe5]+$/;
if (!reg.test (str)) {
Alert ("Sorry, you typed the string type incorrectly!"); /Please replace "string type" with the name of the property you want to verify!
}
}
}

Determine if the input email format is correct
function Isemail ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^\w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *$/;
if (!reg.test (str)) {
Alert ("Sorry, you typed the string type incorrectly!"); /Please replace "string type" with the name of the property you want to verify!
}
}
}

Determine if the input ZIP code (six-bit only) is correct
function Iszip ()
{
var str = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^\d{6}$/;
if (!reg.test (str)) {
Alert ("Sorry, you typed the string type incorrectly!"); /Please replace "string type" with the name of the property you want to verify!
}
}
}

Judging the number entered is not greater than a specific number
function MaxValue ()
{
var val = document.getElementById (' str '). Value.trim ();
if (str.length!=0) {
reg=/^[-+]?\d*$/;
if (!reg.test (str)) {//Determines whether a number type
if (Val>parseint (' 123 '))//"123" for the maximum value set for itself
{
Alert (' Sorry, the number you entered is out of range ');//Please change "number" to the name of the property you want to verify!
}
}
}
}
 
   
  Phone:/^ ((\d{2,3}\) | ( \d{3}\-))? (\ (0\d{2,3}\) |0\d{2,3}-)? [1-9]\d{6,7} (\-\d{1,4})? $/    
 Mobile:/^ (\ (\ d{2,3}\)) | (\d{3}\-))? 13\d{9}$/    
 url:/^http:\/\/[a-za-z0-9]+\.[ a-za-z0-9]+[\/=\?%\ -&_~ ' @[\]\ ': +!] * ([^<>\ "]) *$/  &NBSP;
 idcard:/^\d{15} (\d{2}[ A-za-z0-9])? $/  &NBSP;
 qq:/^[1-9]\d{4,8}$/  < Span class= "Apple-converted-space" >&NBSP;
  Some special amount:/^ ((\d{1,3} (, \d{3}) | ( \d+)) (\.\d{2})?$/              //Description: Except " xxx    xx,xxx    xx,xxx.00 "outside the format

Provide the. Trim () property for each of the JS verification methods provided above
String.prototype.trim=function () {
Return This.replace (/(^\s*) | (   \s*$)/g, "");
}

Call:
<input type= "text" name= "str" >
<input type= "button" value= "OK" onclick= "" >//onclick Write your own JS validation function to invoke

Regular-expression validation