Check textboxes for empty string

[daitasri]

Hi
I m using javascript in HTML. I want to know how to validate the text entered in a textbox (for empty strings). My requirement is that my code should not allow empty text (not even spaces -trailing n leading). I have used some code which is checking only wen v do not enter any text. But its not validating when v enter some number of blank spaces.Please help .
Thanks
daitasri

[vikas1111]

Hi
I m using javascript in HTML. I want to know how to validate the text entered in a textbox (for empty strings). My requirement is that my code should not allow empty text (not even spaces -trailing n leading). I have used some code which is checking only wen v do not enter any text. But its not validating when v enter some number of blank spaces.Please help .
Thanks
daitasri

Please post your code....

[RamananKalirajan]

Hi
I m using javascript in HTML. I want to know how to validate the text entered in a textbox (for empty strings). My requirement is that my code should not allow empty text (not even spaces -trailing n leading). I have used some code which is checking only wen v do not enter any text. But its not validating when v enter some number of blank spaces.Please help .
Thanks
daitasri

Hi, for this you can use String function like indexOf('the string you want to check', and the delimiter like space so and so) - if the delimiter is present it will return the index at which it is present otherwise it will return -1.
I give u a code for email validation. This may be helpful for you

<html>
<head>
<script type="text/javascript">
function validate_email(field,alerttxt)
{
with (field)
{
apos=value.indexOf("@");
dotpos=value.lastIndexOf(".");
if (apos<1||dotpos-apos<2) 
  {alert(alerttxt);return false;}
else {return true;}
}
}function validate_form(thisform)
{
with (thisform)
{
if (validate_email(email,"Not a valid e-mail address!")==false)
  {email.focus();return false;}
}
}
</script>
</head><body>
<form action="submitpage.html"
onsubmit="return validate_form(this);"
method="post">
Email: <input type="text" name="email" size="30">
<input type="submit" value="Submit"> 
</form>
</body></html>

If more doubts means pls post your code

[gits]

hi ...

have a look at the following example, that uses another simple validation method:

[CODE=javascript]// our value
var v = ' 1234 ';

// the validate function
function validate(val) {
// first we trim leading and trailing spaces
val = trim(val);

// now we check for the length of the string
// and return true when v is not an 'empty string'
return val.length != 0;
}

// trim function that uses regex to replace the spaces
function trim(val) {
var ret = val.replace(/^\s+/, '');
ret = ret.replace(/\s+$/, '');

return ret;
}

// it will alert true ... so tha validation says ok ...
alert(validate( v));
[/CODE]
kind regards

[daitasri]

Hi

I used the following code ,which trims any number of leading and trailing spaces. I also want to know how to restrict the number of spaces between two words to one.For example :
It should allow strings like "A bc" but not something like "A bc" or "A bc". Please help me on this.It shud not allow two or more spaces between the two words.
[CODE=javascript] function trim(str)
{

str=str.replace (/^\s*/,"").replace (/\s*$/,"");
alert('user id after trim'+str);
return str;

}[/CODE]

Thanks in Advance
daitasri

[RamananKalirajan]

The following code will remove the white spaces from the begining and end of the String, if it is useful to you just use it

[HTML]<Html>
<head>
<script type="text/javascript">
function Trim(str)
{ while(str.charA t(0) == (" ") )
{ str = str.substring(1 );
}
while(str.charA t(str.length-1) == " " )
{ str = str.substring(0 ,str.length-1);
}
return str;
}
var myString = " This is my string ";
var newString = Trim(myString);
alert("myString length: " + myString.length );
alert(myString) ;
alert("newStrin g length: " + newString.lengt h);
alert(newString );
</script>
</head>
</html>[/HTML]

[gits]

... I also want to know how to restrict the number of spaces between two words to one.For example : It should allow strings like "A bc" but not something like "A bc" or "A bc". Please help me on this.It shud not allow two or more spaces between the two words.
...

here is an example:

[CODE=javascript]var s = 'A bc';

function trim_inner_spc( s) {
s = s.replace(/\s+/g, ' ');
return s;
}

alert(trim_inne r_spc(s));
[/CODE]
use it after trimming the trailing and leading spaces ...

kind regards

[daitasri]

here is an example:

[CODE=javascript]var s = 'A bc';

function trim_inner_spc( s) {
s = s.replace(/\s+/g, ' ');
return s;
}

alert(trim_inne r_spc(s));
[/CODE]
use it after trimming the trailing and leading spaces ...

kind regards

Hi
Thanks a lot .. Its working perfectly.
Regards
daitasri

[gits]

no problem ... post back to the forum anytime you have more questions ...

kind regards