JavaScript common various authentication code encyclopedia (1/5)

Source: Internet
Author: User

1. Length Limit

The code is as follows Copy Code

<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

The code is as follows Copy Code
<input onkeyup= "value="/oblog/value.replace (/[^u4e00-u9fa5]/g, ') ">

3. can only be English

The code is as follows Copy Code

<script language= "JavaScript" >

function Onlyeng ()

{

if (!) ( EVENT.KEYCODE>=65&&EVENT.KEYCODE<=90))

Event.returnvalue=false;

}

</script>


<input onkeydown= "Onlyeng ();" >

4. Only the numbers

The code is as follows Copy Code

<script language=javascript>

function Onlynum ()

{

if (!) ( (event.keycode>=48&&event.keycode<=57) | | (event.keycode>=96&&event.keycode<=105)))

Consider the number keys on the keypad

Event.returnvalue=false;

}

</script>
<input onkeydown= "Onlynum ();" >

5. Only English characters and numbers

The code is as follows Copy Code

<input onkeyup= "value="/oblog/value.replace (/[w]/g, "')"

Onbeforepaste= "Clipboarddata.setdata" (' Text ', Clipboarddata.getdata (' text '). Replace (/[^d]/g, ') ">

6. Verify the fuel tank format

The code is as follows Copy Code

<script Language=javascript runat=server>

function Isemail (stremail) {

if (/^w+ (-w+) | (stremail.search) | (. 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) >

. Shielding Keywords (here block * * * * and * * * *)

The code is as follows Copy Code

<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

The code is as follows Copy Code

<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, right now, that's cool.

The code is as follows Copy Code
Oncontextmenu= ' return false ' ondragstart= ' return false ' onselectstart= ' return false '

Added to the body.


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