By using this site, you agree to our updated Privacy Policy and our Terms of Use. Manage your Cookies Settings.
440,781 Members | 1,134 Online
Bytes IT Community
+ Ask a Question
Need help? Post your question and get tips & solutions from a community of 440,781 IT Pros & Developers. It's quick & easy.

Validator control for text length

P: n/a
Is there a asp.net validator control that validates the length of the text
being entered or does everyone just write jscript for this?

--
mo*******@nospam.com
Nov 18 '05 #1
Share this Question
Share on Google+
4 Replies


P: n/a
You can make use of the RegularExpressionValidator for this purpose

Secondly if you are using a TextBox you can set the MaxLength property

Thanx

Nimish.
Nov 18 '05 #2

P: n/a
Hi Moondaddy,

Thanks for posting here. Based on your description, you 're looking for
some approachs to validate the input fields(textbox)'s value's length on
ASP.NET web pages. You're wondering whether need to use a certain validator
control or just some clientside script block, yes?

As for this question, I think the clientside script is enougth if you don't
need very complex function. For example, we can get a textbox's value's
length via such script:
textbox.value.length
then, we can validate the value as what we want.
And here is an sample on using the javascript to retrieving text field
value's length and do validation on it:
-------------------------------aspx page---------------------------------
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>ValidateLength</title>
<meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">
<meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema"
content="http://schemas.microsoft.com/intellisense/ie5">
<script language=javascript>
function ValidateLength(oid, min, max)
{
var txt = document.getElementById(oid);
var length = txt.value.length;

alert("input's length is " + length);
if(length<min || length>max)
{
alert("Invalidated!");
}
else
{
alert("Validated!");
}
}
</script>
</HEAD>
<body>
<form id="Form1" method="post" runat="server">
<table width="100%" align="center">
<tr>
<td><INPUT id="txtContent" type="text"></td>
<td><INPUT id="btnValidate" type="button" value="Validate"
onclick="ValidateLength('txtContent',4,8)" >(Length must
be limited&nbsp;between 4----8)</td>
</tr>
<tr>
<td></td>
<td></td>
</tr>
</table>
</form>
</body>
</HTML>
------------------------------------------------------------------
NO additional code behind code needed

If you need complex functions on validating, you can also implement them
via javascript if you want to implement them at clientside. In addtion, the
ASP.NET's custom validator control also provide the functions which let you
use Regular expressions to customize your own validation rules. Here is the
related document on it:

#Regular Expression Validator Control Sample
http://msdn.microsoft.com/library/en...larexpressionv
alidatorcontrolsample.asp?frame=true
Please check out the preceding suggestions to see whether they help. If
you have any further questions, please feel free to post here.
Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
Nov 18 '05 #3

P: n/a
Thanks. I tried this sample in a html page and all worked well. then I put
it in my aspx page and called a revised version of the function in an
asp.textbox ontextchaned event and the page errors when it loads saying that
it cant find the function. I put the function in a script file so it can be
used by other pages and here's how I referenced it in the page:
<HEAD>
<title>NewLogin</title>
<meta content="Microsoft Visual Studio .NET 7.1" name="GENERATOR">
<meta content="Visual Basic .NET 7.1" name="CODE_LANGUAGE">
<meta content="JavaScript" name="vs_defaultClientScript">
<meta content="http://schemas.microsoft.com/intellisense/ie5"
name="vs_targetSchema">
<script src="Scripts/Main.js" type="text/javascript"></script>
</HEAD>

I also tried writing the function into some script in the body of page with
no success. Is there anyway I can get this to work by using calling a
function from a script file?

--
mo*******@nospam.com
"Steven Cheng[MSFT]" <v-******@online.microsoft.com> wrote in message
news:aO***************@cpmsftngxa06.phx.gbl...
Hi Moondaddy,

Thanks for posting here. Based on your description, you 're looking for
some approachs to validate the input fields(textbox)'s value's length on
ASP.NET web pages. You're wondering whether need to use a certain validator control or just some clientside script block, yes?

As for this question, I think the clientside script is enougth if you don't need very complex function. For example, we can get a textbox's value's
length via such script:
textbox.value.length
then, we can validate the value as what we want.
And here is an sample on using the javascript to retrieving text field
value's length and do validation on it:
-------------------------------aspx page---------------------------------
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>ValidateLength</title>
<meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">
<meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema"
content="http://schemas.microsoft.com/intellisense/ie5">
<script language=javascript>
function ValidateLength(oid, min, max)
{
var txt = document.getElementById(oid);
var length = txt.value.length;

alert("input's length is " + length);
if(length<min || length>max)
{
alert("Invalidated!");
}
else
{
alert("Validated!");
}
}
</script>
</HEAD>
<body>
<form id="Form1" method="post" runat="server">
<table width="100%" align="center">
<tr>
<td><INPUT id="txtContent" type="text"></td>
<td><INPUT id="btnValidate" type="button" value="Validate"
onclick="ValidateLength('txtContent',4,8)" >(Length must
be limited&nbsp;between 4----8)</td>
</tr>
<tr>
<td></td>
<td></td>
</tr>
</table>
</form>
</body>
</HTML>
------------------------------------------------------------------
NO additional code behind code needed

If you need complex functions on validating, you can also implement them
via javascript if you want to implement them at clientside. In addtion, the ASP.NET's custom validator control also provide the functions which let you use Regular expressions to customize your own validation rules. Here is the related document on it:

#Regular Expression Validator Control Sample
http://msdn.microsoft.com/library/en...larexpressionv alidatorcontrolsample.asp?frame=true
Please check out the preceding suggestions to see whether they help. If
you have any further questions, please feel free to post here.
Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx

Nov 18 '05 #4

P: n/a
Hi Moddady,
Have you had a chance to try out my suggestions and sample? If you have any
questions, please feel free to post here.
Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx

Nov 18 '05 #5

This discussion thread is closed

Replies have been disabled for this discussion.