How to Control the Length of a multiline text box

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How to Control the Length of a multiline text box

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Last post 01-07-2007 11:26 AM by Jigar. 7 replies.

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How to Control the Length of a multiline text box

01-05-2007, 5:18 AM

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sivasravan
Joined on 06-27-2006, 4:43 PM
Posts 2

Hii Smile

I am doing a project dealt with sending SMS ..
So i have to control the length of the message to be sent ..
But for textbox of Multiline type did not allowing the MaxLength property ..
So plz do favour for me regarding this one ...

Thanks a lot in advance

Sravan....

Re: How to Control the Length of a multiline text box

01-05-2007, 7:13 AM

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RikardoB
Joined on 01-03-2007, 5:43 PM
Portugal, Lisbon
Posts 41

Hello Sivasravan!

You have a little problem. Like you said you are using a TEXTBOX with MULTINE type. Using that object is almost the same thing using a TEXTAREA and this object doesn't have MULTINE type too.

My sugestion is using a JAVASCRIPT FUNCTION to count the length of the TEXTBOX. Try this:

<SCRIPT language="text/javascript">
function CountLength(ObjectThatYouWant)

{
LenTxt = ObjectThatYouWant.value.length;
if (LenTxt > 100)

        {
            ObjectThatYouWant.value = ObjectThatYouWant.value.substring(0,100);
        }

}

</SCRIPT>

Then call this function on client side in this button events : onkeydown, onkeyup, onchange, onblur

HAVE NICE DEBUGS!

Re: How to Control the Length of a multiline text box

01-05-2007, 7:16 AM

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RikardoB
Joined on 01-03-2007, 5:43 PM
Portugal, Lisbon
Posts 41

* TEXTAREA doesn´t have MaxLength property...

Re: How to Control the Length of a multiline text box

01-05-2007, 8:29 AM

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akjoshi
Joined on 05-06-2006, 1:23 PM
INDIA
Posts 614

Hi ,

I use this function for restricting length of textarea, chek if it works for you

// Javascript for restricting the maxchars entered in textarea. //

// onkeypress="return maxtext(this, 256, event);"

function maxtext(field, size, e)

{

tempstr = field.value;

if(tempstr.length<size){return true;}

else

{

var key;

if(window.event)

key = e.keyCode;

//IE

else

key = e.which;

//FF

// Allow special characters: BACKSPACE, TAB, RETURN, LEFT ARROW,

// RIGHT ARROW to go through ** Work in IE only

if ((key == 8) || (key == 9) || (key == 32) || (key == 40) || (key == 41) || (key == 43) || (key == 45))// || (key == 13))// || (key == 32))

return true;

}

return false;

}

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Re: How to Control the Length of a multiline text box

01-05-2007, 10:16 AM

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pushp_aspnet
Joined on 10-19-2006, 1:27 PM
Hyderabad,India
Posts 447

Hi,

checkout this link: http://www.dynamicdrive.com/dynamicindex16/maxlength.htm

Hope this helps.

Home Is Where the Wind Blows
http://pushpontech.blogspot.com

Re: How to Control the Length of a multiline text box

01-05-2007, 10:51 AM

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haoest
Joined on 10-25-2005, 8:20 PM
Posts 403

make sure you understand that checking on client side is only half of the work. You have to make sure the message is within specified length on server side, too.

Debugger is my best friend. (http://haoest.info)

Re: How to Control the Length of a multiline text box

01-07-2007, 7:21 AM

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NC01
Joined on 08-26-2005, 3:33 PM
Posts 9,403

In the server-side Page_Load event handler:
TextBox1.Attributes.Add("maxCharacters", "3");
TextBox1.Attributes.Add("onblur", "if ( this.value.length > this.maxCharacters ) {alert('Too many characters!'); this.value = this.value.substr(0, this.maxCharacters);}");

NC...

Re: How to Control the Length of a multiline text box

01-07-2007, 11:26 AM

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Jigar
Joined on 06-17-2002, 5:41 AM
Ridgewood, NJ
Posts 935

How about using RegularExpressionValidator to validate length of TextBox it will also take care of serverside validation. following sample code shows how to use that.

Run sample code

1    <%@ Page Language="C#" %>
2    <html>
3    <head id="Head1" runat="server">
4        <title>Multiline Textbox max length</title>
5    </head>
6    <body>
7        <form id="form1" runat="server">
8        <div>
9            <p>Only 25 chars Please!</p>
10           <asp:TextBox runat="server" ID="MLTextBox" 
11               TextMode="MultiLine" width="400"></asp:TextBox>
12           <asp:RegularExpressionValidator 
13                   runat="server" Display="dynamic" 
14                   ControlToValidate="MLTextBox" 
15                   ValidationExpression="^([\S\s]{0,25})$" 
16                   ErrorMessage="p>">
17           </asp:RegularExpressionValidator>
18           <p />
19           <asp:Button ID="Button1" runat="server" text="Submit"/>
20       </div>
21       </form>
22   </body>
23   </html>