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HomeWeb Front-endJS TutorialSome commonly used Javascript judgment functions_Basic knowledge

1.

This is an DIV





2. Javascript error
Copy code The code is as follows:

w1=0;
w1 =Math.round(1333333.99*100 );
w1 =Math.round(13663.38*100);
document.write(w1/100);
w1=0;
w1 =1333333.99;
w1 =13663.38;
document.write(w1);

3. Form check
Copy code The code is as follows :

//wanghui added a function checkPort() in 20031020 to check the business access and processing address port number;
function toChnDigit(num)
{
var t = parseInt(num) ;
if(t==0) return "zero";
if(t==1) return "one";
if(t==2) return "two";
if (t==3) return "三";
if(t==4) return "四";
if(t==5) return "五";
if(t==6 ) return "six";
if(t==7) return "seven";
if(t==8) return "eight";
if(t==9) return "nine" ;
return "";
}
//@CheckItem@ OPT-HuTie-20031208 Optimization: Add a public function to disable all buttons
function disableAllButtons(){
for(var i= 0;ivar tmp = document.all.tags("input")[i];
if(tmp.type== "button" || tmp.type=="submit" ||tmp.type=="reset"){
tmp.disabled = true;
}
}
}
/ /Add trim function
String.prototype.trim = function()
{
return this.replace(/(^s*)|(s*$)/g, "");
}
//Function name: checkNUM
//Function introduction: Check whether it is a number
//Parameter description: The number to be checked
//Return value: 1 means it is a number, 0 means it is not Number
function checkNum(Num) {
var i,j,strTemp;
strTemp = "0123456789.";
if (Num.length == 0)
return 0
for (i = 0;i j = strTemp.indexOf(Num.charAt(i));
if (j == -1) {
// Indicates that there is a character that is not a number
return 0;
}
}
//Indicates that it is a number
return 1;
}
//Function name: checkNUM
/ /Function introduction: Check whether it is a number
//Parameter description: The number to be checked
//Return value: 1 means it is a number, 0 means it is not a number
function checkIntNum(Num) {
var i,j,strTemp;
strTemp = "0123456789";
if ( Num.length == 0)
return 0
for (i = 0;i j = strTemp.indexOf(Num.charAt(i));
if (j == -1) {
//Indicates that there are characters that are not numbers
return 0;
}
}
//The description is a number
return 1;
}
//Function name: checkEmail
//Function introduction: Check whether it is an Email Address
//Parameter Description: String to be checked
//Return value: 0: Not 1: Yes
function checkEmail(a) {
//@CheckItem@ Bug141-hutie-20030821 Modify interface: Email address needs to be done Disable Chinese verification
var reg = /[^u0000-u00FF]/;
if(a.match(reg)!=null){
return 0;//There are Chinese characters
}
var i=a.length;
var temp = a.indexOf('@');
var tempd = a.indexOf('.');
if (temp > 1) {
if ((i-temp) > 3){
if ((i-tempd)>0){
return 1;
}
}
}
return 0;
}
//Function name: checkTEL
//Function introduction: Check whether it is a phone number
//Parameter description: The string to be checked
//Return value : 1 means legal, 0 means illegal
function checkTel(tel)
{
var i,j,strTemp;
strTemp = "0123456789- ()";
for (i =0;i{
j = strTemp.indexOf(tel.charAt(i));
if (j==-1)
{
//Indicates that there are characters that are illegal
return 0;
}
}
//Indicates that the characters are legal
return 1;
}
//Function name: checkLength
//Function introduction: Check the length of the string
//Parameter description: The string to be checked
//Return value: Length value
function checkLength(strTemp)
{
var i ,sum;
sum = 0;
for(i=0;i{
//@CheckItem@ BUG-Renhj-20040604 Optimization: Function that will be verified Change it to 128 to use a single character.Avoid the "·" symbol
// if ((strTemp.charCodeAt(i)>=0) && (strTemp.charCodeAt(i)if ((strTemp.charCodeAt(i) >=0) && (strTemp.charCodeAt(i)sum = sum 1;
else
sum = sum 2;
}
return sum;
}
//Function name: checkSafe
//Function introduction: Check whether it contains "'", '"',"", ";", ","
//Parameter description: String to be checked
//Return value: 0: Yes 1: No
function checkSafe(a)
{
fibdn = new Array ("'",' "',">", "i = fibdn.length;
j = a.length;
for (ii=0;ii< ;i;ii )
{
for (jj=0;jj{
temp1 = a.charAt(jj);
temp2 = fibdn[ii];
if (temp1==temp2)
{
return 0;
}
}
}
return 1;
}
//Function name: checkChar
//Function introduction: Check whether it contains non-alphabetic characters
//Parameter description: The string to be checked
//Return value: 0: Contains 1: All letters
function checkChar( str)
{
var strSource ="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.()& ";
var ch;
var i;
var temp;
for (i=0;i{
ch = str.charAt(i);
temp = strSource.indexOf(ch);
if (temp==-1)
{
return 0;
}
}
return 1;
}
//Function name: checkCharOrDigital
//Function introduction: Check whether it contains non-digit or Letter
//Parameter description: String to be checked
//Return value: 0: Contains 1: All numbers or letters
function checkCharOrDigital(str)
{
var strSource = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.()& ";
var ch;
var i;
var temp; >{
ch = str.charAt(i);
temp = strSource.indexOf(ch);
if (temp == -1)
{
return 0;
}
}
return 1;
}
//Function name: checkChinese
//Function introduction: Check whether it contains Chinese characters
//Parameter description: String to be checked
//Return value: 0: Contains 1: No
function checkChinese(strTemp)
{
var i,sum;
for(i=0;i{
if ((strTemp.charCodeAt(i)255))
return 0;
}
return 1;
}
//Function name: compareTime()
//Function introduction: Compare time size
//Parameter description: beginYear starts year, beginMonth starts month, benginDay starts day, beginH starts hour, beginM start minute,
// endYear end year, endMonth end month, endMonth end day, endH end hour, endM end minute
//Return value: true means the start time is greater than the end time, false on the contrary
function compareTime(beginYear,beginMonth,benginDay,beginH,beginM,endYear,endMonth,endDay,endH,endM){
var date1 = new Date(beginYear,beginMonth-1,benginDay,beginH,beginM);
var date2 = new Date(endYear,endMonth-1,endDay,endH,endM);
if(date1.getTime()>date2.getTime()){
return false;
}
return true;
}
//Function name: compareDate()
//Function introduction: Compare date size
//Parameter description: beginYear starts year, beginMonth starts month, benginDay starts day
//endYear ends the year, endMonth ends the month, endMonth ends the day
//Return value: 0: true means the start time is greater than the end time, false on the contrary
function compareDate(beginYear,beginMonth,benginDay,endYear,endMonth,endDay ){
var date1 = new Date(beginYear,beginMonth-1,benginDay);
var date2 = new Date(endYear,endMonth-1,endDay);
if(date1.getTime()> date2.getTime()){
return false;
}
return true;
}
//Function name: checkUrl
//Function introduction: Check whether the Url is legal
//Parameter description: String to be checked
//Return value: true: legal false: illegal.
function checkURL(strTemp)
{
if(strTemp.length==0) return false;
if(checkChinese(strTemp)==0) return false;
if (strTemp.toUpperCase().indexOf("HTTP://") != 0 && strTemp.toUpperCase().indexOf("HTTPS://") != 0){
return false;
}
return true;
}
// @CheckItem@ OPT-Renhj-20030704 提供公共的去处空格的方法
//清除左边空格
function js_ltrim(deststr)
{
if(deststr==null)return "";
var pos=0;
var retStr=new String(deststr);
if (retStr.lenght==0) return retStr;
while (retStr.substring(pos,pos 1)==" ") pos ;
retStr=retStr.substring(pos);
return(retStr);
}
//清除右边空格
function js_rtrim(deststr)
{
if(deststr==null)return "";
var retStr=new String(deststr);
var pos=retStr.length;
if (pos==0) return retStr;
while (pos && retStr.substring(pos-1,pos)==" " ) pos--;
retStr=retStr.substring(0,pos);
return(retStr);
}
//清除左边和右边空格
function js_trim(deststr)
{
if(deststr==null)return "";
var retStr=new String(deststr);
var pos=retStr.length;
if (pos==0) return retStr;
retStr=js_ltrim(retStr);
retStr=js_rtrim(retStr);
return retStr;
}
//格式化输入的日期串,输入的如:"2003-9-12" 输出:"2003-09-12"
function formatDateStr(inDate){
if (inDate==null||inDate=="") return "";
var beginDate = inDate.split("-");
var mYear=beginDate[0];
var mMonth=beginDate[1];
var mDay=beginDate[2];
mMonth=((mMonth.length==1)?("0" mMonth):mMonth);
mDay=((mDay.length==1)?("0" mDay):mDay);
return mYear "-" mMonth "-" mDay;
}
//Added by wanghui 20031020 检查URL地址的端口的合法性,必须为小于65535的数字
function checkPort(inValue1,inValue2){
//先检查第一个参数的合法性,如果第二个参数是null,则第一个参数表示短信业务的‘业务处理地址'
if(inValue1 != null && inValue1.value != ""){
var array1 = inValue1.value.split(":");
if(array1.length >=4){ //如果以':'分割数组长度为四,则有两个':',所以不合法。
if(inValue2==null) alert("Business processing address port format error");
else alert("Business access address port format error");
inValue1.focus();
return false;
}
if(array1.length >= 3) {
port1 = array1[2];
if ((pos1 = port1.indexOf("/")) > = 0){ //Check whether there is a '/' after the port. If there is, the port before this symbol is the port
port1 = port1.substring(0,pos1)
}
if ( port1 == "" || checkIntNum(port1) == 0 || port1>65535){
if(inValue2 == null) alert("Business processing address port must be a number and cannot be greater than 65535");
else alert ("The business access address port must be a number and cannot be greater than 65535");
inValue1.focus();
return false;
}
}
}
//Check again Legality of the second parameter
if(inValue2 != null && inValue2.value != ""){
var array2 = inValue2.value.split(":");
if(array2. length >=4){
alert("Business processing address port format error");
inValue2.focus();
return false;
}
if(array2.length > ;= 3) {
port2 = array2[2];
if ((pos2 = port2.indexOf("/")) >= 0){
port2 = port2.substring(0,pos2 )
}
if ( port2 == "" || checkIntNum(port2) == 0 || port2>65535){
alert("Business processing address port must be a number and cannot be greater than 65535") ;
inValue2.focus();
return false;
}
}
}
return true;
}
//obj: data object
//dispStr: Failure prompt content display string
function checkUrlValid( obj, dispStr)
{
if(obj == null)
{
alert("The incoming object is empty" );
return false;
}
var str = obj.value;
var urlpatern0 = /^https?://. $/i;
if(!urlpatern0.test( str))
{
alert(dispStr "Illegal: must start with 'http://' or 'https://'!");
obj.focus();
return false;
}
var urlpatern2= /^https?://(([a-zA-Z0-9_-]) (.)?)*(:d )?. $/i;
if(!urlpatern2.test(str))
{
alert(dispStr "The port number must be a number and should be between 1-65535!");
obj.focus();
return false;
}
var urlpatern1 =/^https?://(([a-zA-Z0-9_-]) (.)?)*(:d )?(/((. )?(?)?=?&?[a-zA-Z0-9_-](?)?)*)*$/i;
if(!urlpatern1.test(str))
{
alert(dispStr "Illegal, please check!");
obj.focus();
return false;
}
var s = "0";
var t = 0;
var re = new RegExp(":\d ","ig");
while((arr = re.exec(str))!=null)
{
s = str.substring(RegExp.index 1,RegExp.lastIndex);
if(s.substring(0,1)=="0")
{
alert(dispStr "The port number cannot start with 0 !");
obj.focus();
return false;
}
t = parseInt(s);
if(t65535)
{
alert(dispStr "The port number must be a number and should be between 1-65535!");
obj.focus();
return false;
}
}
return true;
}
//Function name: checkVisibleEnglishChr
//Function introduction: Check whether English characters can be displayed (!"#$%&'()*,-./0123456789: ;?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[]^_`abcdefghijklmnopqrstuvwxyz{|}~)
//Parameter description: String to be checked
//Return value: true|false
//add by renhj 2004.01.05
function checkVisibleEnglishChr(strTemp)
{
var i;
for(i=0;i{
if (( strTemp.charCodeAt(i)126))
return false;
}
return true;
}
//Function Name: checkInputChr
//Function introduction: Check whether it contains non-Input characters
//Parameter description: The string to be checked
//Return value: false: Contains true: All characters can be input
//add by renhj 2004.01.05
function checkInputChr(str)
{
var notinput = ""'";
var i;
for (i = 0 ; notinput != null && i if (str.indexOf(notinput.charAt(i)) >= 0) {//If any
return false;
}
}
return true;
}
//Function name: checkTelExt
//Function introduction: Check whether it is a phone number and there is no extension
//Parameter description : The string to be checked
//Return value: 1 is legal, 0 is illegal
function checkTelExt(tel)
{
var i,count,isNumber;
count = 0; //There are several consecutive number strings
isNumber = 0; //Not a number
for (i=0;i{
//Judge the current Is number
if(checkIntNum(tel.charAt(i)) == 1)
{
if(isNumber == 0)
{
count = count 1;
}
isNumber = 1;
}else{
isNumber = 0;
}
if (count > 2)
{
//Indicates that some characters are illegal or have Extension number
return 0;
}
}
if((checkIntNum(tel.charAt(0)) == 1)&&
(checkIntNum(tel.charAt(tel.length- 1)) == 1)){
//It means it is legal
return 1;
}else{
//It means there are characters that are illegal
return 0;
}
}
//Function name: checkFormdata
//Function introduction: Check Form object
//Parameter description:
//obj: object to be checked,
//name: to be checked The Chinese name of the object,
//length: the length of the object being checked (//notnull: if it is true, it is checked to be non-null,
//notSpecChar: if it is true, it is checked Are there any special characters?
//notChinessChar: If true, check whether there are Chinese characters.
//numOrLetter: If true, the check can only be numbers or English letters.
//pNumber: If true, then The check can only be positive integers,
//Return value: false: The check fails true: All characters can be input
//add by renhj 2004.03.19
//@CheckItem@ BUG:1641: 718-Renhj-20040902-Add5 Modify check digit information
function checkFormdata(obj,name,length,notnull,notSpecChar,notChinessChar,numOrLetter,pNumber){
//Check object
if (!obj ) {alert("The target is not an object, processing failed!"); return false;}
var msg;
var ilen;
//Detect Chinese characters
if (notChinessChar&&(checkChinese(obj.value ) != 1)){
msg=name "Cannot contain Chinese characters!";
alert(msg);
obj.focus();
return false;
}
//Detect special characters
if(notSpecChar&&(!checkInputChr(obj.value))){
var notinput = ""'";
msg=name "Illegal characters (" notinput ")! ";
alert(msg);
obj.focus();
return false;
}
//Check length
if(length>=0&&(checkLength(obj. value)>length)){
ilen=length/2;
if(pNumber){
msg=name "cannot exceed " length "numbers! ";
}else if(notChinessChar){
msg=name "cannot exceed " length " English words! ";
}else{
msg=name "cannot exceed " length " English or " ilen " Chinese characters! ";
}
alert(msg);
obj.focus();
return false;
}
//Detect non-null
if(notnull&&obj.value= =""){
msg="Please enter " name "! ";
alert(msg);
obj.focus();
return false;
}
//The detection can only be numbers or English letters
re = /[W_ ]/;
if (numOrLetter&&re.exec(obj.value)) {
msg=name "can only be numbers or English letters! ";
alert(msg);
obj.focus();
return false;
}
//Detection can only be positive integers
re = /[ D_]/;
if (pNumber&&re.exec(obj.value)) {
msg=name "can only be positive integers! ";
alert(msg);
obj.focus();
return false;
}
return true;
}
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