JavaScript Common Judgment Writing Encyclopedia (recommended) _javascript skills

JS verification Form Daquan, with JS control form submission, the specific content as follows:

1. Length Limit

<script>
function Test () 
{
if (document.a.b.value.length>50)
{
alert ("Cannot exceed 50 characters!") ");
Document.a.b.focus ();
return false;
}
}
</script>
<form name=a onsubmit= "return Test ()" >
<textarea name= "B" cols= "" wrap= "VIRTUAL "Rows=" 6 "></textarea>
<input type=" Submit "name=" Submit "value=" Check ">
</form>

2. Can only be Chinese characters

<input onkeyup= "value="/oblog/value.replace (/[^u4e00-u9fa5]/g, ') ">

3. "Can only be English

<script language=javascript>
function Onlyeng ()
{
if (!) ( event.keycode>=65&&event.keycode<=90))
Event.returnvalue=false
}
</script><input onkeydown= "Onlyeng ();" >

4. Only the numbers

<script language=javascript>
function onlynum ()
{
if (!) ( (event.keycode>=48&&event.keycode<=57) | | (event.keycode>=96&&event.keycode<=105)))
Consider the numeric key event.returnvalue=false on the keypad
;
</script>
<input onkeydown= "Onlynum ();" >

5. Only English characters and numbers

<input onkeyup= "value="/oblog/value.replace (/[w]/g, "'") "onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^d]/g, ') ">

6. Verify the mailbox format

<script language=javascript runat=server>
function Isemail (stremail) {
if (stremail.search) ((/^w+) | (. w+)) *@[a-za-z0-9]+ (. | -) [a-za-z0-9]+] *. [a-za-z0-9]+$/)!=-1) return
true;
else
alert ("Oh");
}
</SCRIPT>
<input type=text onblur=isemail (this.value) >

7. Shielding keywords (here shield * * * * and * * * *)

<script language= "javascript1.2" >
function Test () {
if (a.b.value.indexof ("* *") = = 0) | | (A.b.value.indexof ("* * *") = = 0)) {
alert (":)");
A.b.focus ();
return false;}
}
</script>
<form name=a onsubmit= "return Test ()" >
<input type=text name=b>
< Input type= "Submit" name= "Submit" value= "Check" >
</form>

8. Two times input password is the same

<form method=post action= "" >
<input type= "password" id= "input1" > <input type= "password" id= "
Input2 ">
<input type=" button "value=" Test "onclick=" Check () ">
</FORM>
<script>
function Check ()
{with 
(document.all) {
if (input1.value!=input2.value)
{
alert ("false")
Input1.value = "";
Input2.value = "";
}
else Document.forms[0].submit ();
}
}
</script>

That's enough,:).

Shielding right button is cool

Oncontextmenu= ' return false ' ondragstart= ' return false ' onselectstart= ' return false '

Added to the body.

http://hovertree.com/menu/javascript/

2.1 Form items cannot be empty

<script language= "JavaScript" >
<!--
function Checkform ()
{ 
if ( Document.form.name.value.length = = 0) { 
alert ("Please enter your name!");
Document.form.name.focus ();
return false;
}
return true;
}
-->
</script>

2.2 Compare the values of two table items

<script language= "JavaScript" >
<!--
function checkform ()
if (Document.form.PWD.value!= Document.form.PWD_Again.value) { 
alert ("The password you entered two times is different!") Please re-enter. ");
Document. ADDUser.PWD.focus ();
return false;
}
return true;
}
-->
</script>

2.3 Form items can only be numbers and "_" for phone/bank account verification, can be extended to domain name registration, etc.

<script language= "JavaScript" >
<!--
function Isnumber (String)
{ 
var letters = ' 1234567890- "; You can add your own input value
var i;
var C;
if (String.charat (0) = = '-') return
false;
if (String.charat (string.length-1) = = '-') return
false;
for (i = 0; i < string.length i + +)
{ 
c = string.charat (i);
if (Letters.indexof (c) < 0) return
false;
}
return true;
}
function Checkform ()
{ 
if (! Isnumber (Document.form.TEL.value)) { 
alert ("Your phone number is illegal!) ");
Document.form.TEL.focus ();
return false;
}
return true;
}
-->
</script>

2.4 Table Single input value/length limit

<script language= "JavaScript" >
<!--
function Checkform () 
{ 
if (document.form.count.value > 100 | | Document.form.count.value < 1)
{ 
alert ("Input value cannot be less than 0 greater than 100!");
Document.form.count.focus ();
return false;
}
if (document.form.message.value.length<10)
{ 
alert ("Input text is less than 10!");
Document.form.MESSAGE.focus ();
return false;
}
return true;
}
-->
</script>

2.5 Chinese/English/digital/email address legality judgment

<script language= "JavaScript" > <!--function isenglish (name)//English value detection {if (name.length = 0) return false; i = 0; i < name.length;
i++) {if (Name.charcodeat (i) > 128) return false; function Ischinese (name)//Chinese value detection {if (name.length = 0) return false; for (i = 0; i < name.length; i++) {if (name.c
Harcodeat (i) > 128) return true;
return false;
function IsMail (name)//e-mail value detection {if (! Isenglish (name)) return false; i = Name.indexof (' at ');
j = Name Dot LastIndexOf ("at");
if (i = = 1) return false;
if (i!= j) return false;
if (i = = Name dot length) return false;
return true; The function isnumber (name)//value detection {if (name.length = 0) return is false; for (i = 0; i < name.length; i++) {if (Name.cha RAt (i) < "0" | |
Name.charat (i) > "9") return false;
return true; The function Checkform () {if (! isMail. Email.value)) {alert ("Your email is illegal!)
"); Form.
Email.focus ();
return false; } if (! Isenglish (Form.name.value)) {alert ("Invalid English name!)"
"); FOrm.name.focus ();
return false; } if (! Ischinese (Form.cnname.value)) {alert ("Chinese name is not legal!")
");
Form.cnname.focus ();
return false; The IF (! Isnumber () Form. Publiczipcode.value)) {alert ("ZIP code not valid!)"
"); Form.
Publiczipcode.focus ();
return false;
return true; }//--> </SCRIPT>

2.6 Qualifying A form item cannot enter characters

<script language= the "javascript" >
<!--

function contain (str,charset)//string contains the test function
{ 
var i;
for (i=0;i<charset.length;i++)
if (Str.indexof (Charset.charat (i)) >=0) return
true;
return false;
}

function Checkform ()
{ 
if (contain (Document.form.NAME.value,% () ><)) | | (Contain (Document.form.MESSAGE.value, "% () ><"
)) { 
alert ("entered an illegal character");
Document.form.NAME.focus ();
return false;
}
return true;
}
-->
</script>

1. Check whether a string of strings is all composed of numbers

<script language= "Javascript" ><!-- 
function Checknum (str) {return Str.match (/d/) ==null} 
alert ( Checknum ("1232142141")) 
alert (Checknum ("123214214A1")) 

2. How to judge whether it is a character

if (/[^x00-xff]/g.test (s)) alert ("contains Chinese characters"); 

3. How to judge whether to contain Chinese characters

if (Escape (str). IndexOf ("%u")!=-1) alert ("contains Chinese characters"); 

4. Mailbox Format Verification

Function Name: Chkemail// 
feature Introduction: Check whether for email 
address//Parameter description: To check the string 
//return value: 0: Not 1: is a 
function Chkemail (a) 
{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; 

5. Digital format Verification

Function Name: Fucchecknum//Feature Description: Check if the number// 
parameter descriptions: To check the number 
//return value: 1 is a number, 0 is not a digital 
function Fucchecknum (NUM) 
{ 
var i,j,strtemp; 
strtemp= "0123456789"; 
if (num.length== 0) return 
0 for 
(i=0;i<num.length;i++) 
{ 
j=strtemp.indexof (Num.charat (i)); 
if (j==-1) 
{ 
//indicates that a character is not a number return 
0; 
} 
} Description is the number return 
1; 

6. Telephone Number format verification

Function Name: Fucchecktel// 
features: Check for phone number 
//Parameter description: To check the string 
//return value: 1 is valid, 0 is an illegal function 
Fucchecktel ( TEL) 
{ 
var i,j,strtemp; 
Strtemp= "0123456789-()"; 
for (i=0;i<tel.length;i++) 
{ 
j=strtemp.indexof (Tel.charat (i)); 
if (j==-1) 
{ 
//Description There is a character not valid return 
0; 
} 
} 
Description legal return 
1; 

7. A function to determine whether the input is Chinese

function Ischinese (s) { 
var ret=true; 
for (Var i=0;i<s.length;i++) 
Ret=ret && (s.charcodeat (i) >=10000); 
return ret; 

8. A comprehensive function to judge the legality of user input

<script language= "JavaScript" > 
//Limit the number of digits of the input character start 
//m is user input, n is the number of digits to restrict 
function Issmall (m,n) 
{ 
if ((m<n) && (m>0 
) {return 
(false); 
} 
else 
{return (true);} 

9. Determine whether the password is entered in a consistent

function Issame (STR1,STR2) 
{ 
if (STR1==STR2) 
{return (true);} 
else 
{return (false);} 

10. Determine if the user name is a digital letter down line

function Notchinese (str) { 
var reg=/[^a-za-z0-9_]/g 
if (reg.test (str)) {return 
(false); 
} else{return 
(TRUE);} 

Universal check function for 2.8. form text Field

Function: Detects all input text that must be non-null, such as name, account number, email address, etc.

The checksum is now only for text fields, and if you want to target other domain objects in the form, you can change the criteria for judgment.

How to: Add title text to the text field you want to detect. The text is in the prompt message, you want to prompt the user with the Chinese name of the field. For example, to detect user names
HTML follows <input name= "txt_1" title= "name", and, of course, it's best to edit the domain with visual tools such as Dreamweaver or something.

If you want to detect numeric types of data, then the domain ID unified to SZ.

JavaScript to determine the date type is more cumbersome, so there is no date-type validation program. The master can be added.

Program to compare grass, just to provide a train of thought. Initiate ：）

Oh, yes, function call method:< form onsubmit= "return Dovalidate ()" >

function Dovalidate ()
{
fm=document.forms[0]//Only detects a form if multiple can change the criteria for
(i=0;i<fm.length;i++)
{ 
//detection criteria, depending on the type can be modified
if (fm[i].tagname.touppercase () = = "INPUT" &&fm[i].type.touppercase () = = "TEXT" && (fm[i].title!= ""))
if (fm[i].value= "/blog/=")//
{
str_warn1=fm[i].title+ "cannot be empty!";
alert (STR_WARN1);
Fm[i].focus ();
return false; 
}
if (fm[i].id.touppercase () = = "SZ")//Digital checksum
{
if (isNaN (fm[i].value))
{str_warn2=fm[i].title+ "wrong format";
alert (str_warn2);
Fm[i].focus ();
return false;
}} return true;
}

The above content is small set to everyone daily collection of JavaScript commonly used to judge the writing encyclopedia, I hope to help you, if you are interested in this article collection, easy to find later!