I know there is a property called Rows and Multiline. But the
Rows property is only a display type property. It doesn't actually prevent the user from entering more than 4 lines if it is set to 4 Rows.
Can anyone suggest a way of preventing the user from entering more than 4 lines of text in a textbox?
Thanks for the code! However, isn't this just to check for a maximum length which can already be achieved using the MaxLength property?
I need to prevent more than 4 lines being entered, effectively preventing more than 4 carriage returns in a textbox. Shame this isn't already implemented as a property like MaxLines or something?
function ValidateLines(e, max)
{
var text = e.value.replace(/\s+$/g,""); // trim trailing white-space characters if you only want to count lines with text in
var split = text.split("\n");
if (split.length > max)
{
alert("You've entered too many lines!!!");
}
}
If you wanted I think you could also get the max number of rows from the Rows value in your textbox instead of passing it in as an argument, e.g.
function ValidateLines(e) { var max = e.rows; var text = e.value.replace(/\s+$/g,""); // trim trailing white-space characters if you only want to count lines with text in var split = text.split("\n"); if (split.length > max) { alert("You've entered too many lines!!!"); } }
"Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us."
That is a better solution, but I noticed 2 things:
1) how come if you just enter CRs and no text it doens't pick up on the maximum lines?
2) one of my buttons doesn't seem to respond, no OnClick fired, whereas another button does fire??
1) Yes, didn't spot that one, as I am playing with it, there are other problems
Not sure what you mean about the onclick ... try taking out the section of the script regarding function---below---
function addLoadEvent(func) {
var oldonload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
} else {
window.onload = function() {
if (oldonload) {
oldonload();
}
func();
}
}
}
addLoadEvent(
function () {
document.amada.subjects.onkeyup = function () {
cleanUpList(document.amada.subjects);
}
}
);
Another problem I found is that if you are using word wrap, the lines a re not counted, but all as 1 line, so you get halfway along the next line and it prevents entering anymore text, until you CR !
I still looking for a solution to this, and have been for 2 days ! it is more of a javascript thing, than an ASP though....
Hokies had the same problem with this with text box trying to pass to flash where the text apears for a print label. Managed to find a solution to this one let me know if it works for you ;)
<
script
type="text/javascript"> var alert_title='Input
Restriction'; function limitTextarea(textarea,maxLines,maxChar)
{ var lines=textarea.value.replace(/\r/g,'').split('\n'),
lines_removed,
char_removed,
i; if(maxLines&&lines.length>maxLines)
{
alert('You can not enter\nmore than '+maxLines+'
lines');
lines=lines.slice(0,maxLines);
lines_removed=1
} if(maxChar)
{
i=lines.length; while(i-->0)if(lines[i].length>maxChar)
{
lines[i]=lines[i].slice(0,maxChar);
char_removed=1
} if(char_removed)
{
alert('You can not enter more\nthan '+maxChar+'
characters per line')
} if(char_removed||lines_removed)
{
textarea.value=lines.join('\n')
} function watchTextarea()
{
document.getElementById('resticted').onkeyup()
} function set_ie_alert()
{
window.alert=function(msg_str)
{
vb_alert(msg_str)
}
}
}
}
</script>
Hokies sorry about the messy code and you will have to remove the alerts as they are tackey and you wouldnt want your user to see them i just used them for testing purposes.
Member
93 Points
592 Posts
How do you limit number of rows in a textbox?
Apr 23, 2008 05:28 AM|swaino|LINK
I know there is a property called Rows and Multiline. But the Rows property is only a display type property. It doesn't actually prevent the user from entering more than 4 lines if it is set to 4 Rows.
Can anyone suggest a way of preventing the user from entering more than 4 lines of text in a textbox?
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102952 Points
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Re: How do you limit number of rows in a textbox?
Apr 23, 2008 05:43 AM|vinz|LINK
Validate the Max Length limit instead.. see below for demo
<script type="text/javascript" language="javascript">
function validatelimit(obj, maxchar)
{
if(this.id) obj = this;
var remaningChar = maxchar - obj.value.length;
document.getElementById('<%= Label1.ClientID %>').innerHTML = remaningChar;
if( remaningChar <= 0)
{
obj.value = obj.value.substring(maxchar,0);
alert('Character Limit exceeds!');
return false;
}
else
{return true;}
}
</script>
<body runat="server">
<form id="form1" runat="server">
<asp:TextBox ID="TextBox1" runat="server" TextMode="MultiLine" onkeyup="validatelimit(this,300)"></asp:TextBox>
<asp:Label ID="Label1" runat="server" Text="0"></asp:Label>
</form>
</body>
300 is the MAX length of the characters in the TextBox..Just change the value of 300 based on your requirements..
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592 Posts
Re: How do you limit number of rows in a textbox?
Apr 23, 2008 05:50 AM|swaino|LINK
Thanks for the code! However, isn't this just to check for a maximum length which can already be achieved using the MaxLength property?
I need to prevent more than 4 lines being entered, effectively preventing more than 4 carriage returns in a textbox. Shame this isn't already implemented as a property like MaxLines or something?
Contributor
4954 Points
1726 Posts
Re: How do you limit number of rows in a textbox?
Apr 23, 2008 05:55 AM|thirumaran007|LINK
Hi Friend,
you can use TextArea instead of textbox to achieve this
kinldy see the sample inline code
<
textarea id="txttest" rows="10"></textarea>here the row indicats the number of rows.
With Friendly,
Thirumaran
Contributor
4660 Points
1011 Posts
Re: How do you limit number of rows in a textbox?
Apr 23, 2008 06:01 AM|ramblor|LINK
This just sets the number of rows being displayed, not the maximum number of rows that can be entered (this was mentioned in the OP).
Contributor
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1011 Posts
Re: How do you limit number of rows in a textbox?
Apr 23, 2008 06:16 AM|ramblor|LINK
Here's a rough solution:
function ValidateLines(e, max) { var text = e.value.replace(/\s+$/g,""); // trim trailing white-space characters if you only want to count lines with text in var split = text.split("\n"); if (split.length > max) { alert("You've entered too many lines!!!"); } }Member
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Re: How do you limit number of rows in a textbox?
Apr 23, 2008 07:12 AM|ajmalmcs1|LINK
hi you can try this code with line and text length restrictions
<%
@ Page Language="VB" AutoEventWireup="false" CodeFile="Default2.aspx.vb" Inherits="Default2" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><
html xmlns="http://www.w3.org/1999/xhtml" ><
head runat="server"> <title>Untitled Page</title>
<script language="javascript">
function ValidateLines(e, max,chrln){
var text = e.value.replace(/\s+$/g,""); var split = text.split("\n"); if (split.length <= max && text.length <=chrln){
return true;}
else if (split.length >= max || e.value.length >=chrln ){
alert(
"stop lines!!!"); return false;}
}
</script>
</head><
body> <form id="form1" runat="server"> <div> <asp:TextBox ID="TextBox1" runat="server" TextMode="MultiLine" Rows="4" onkeypress="return ValidateLines(this,4,30)"/>
</div> </form></
body></
html>Member
93 Points
592 Posts
Re: How do you limit number of rows in a textbox?
Apr 24, 2008 10:46 AM|swaino|LINK
Hi,
Good solutions thanks, but I'm wondering why the keypress still gets sent to the textbox even when it is over the maximum number of lines?
Member
20 Points
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Re: How do you limit number of rows in a textbox?
Apr 24, 2008 11:00 AM|auztin100|LINK
I have a similar requirement for this, also with the above solution, you can no longer edit any of the text ....
Thanks guys
Member
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Re: How do you limit number of rows in a textbox?
Apr 24, 2008 11:17 AM|auztin100|LINK
Hi there, well I found some javascript that works well, just ignore the onload part, and add a onkey="cleanUpList(this)" function to your text area.
http://javascript.internet.com/forms/limit-textarea-2.html
Member
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Re: How do you limit number of rows in a textbox?
Apr 24, 2008 11:45 AM|swaino|LINK
Hi,
That is a better solution, but I noticed 2 things:
1) how come if you just enter CRs and no text it doens't pick up on the maximum lines?
2) one of my buttons doesn't seem to respond, no OnClick fired, whereas another button does fire??
Member
20 Points
3 Posts
Re: How do you limit number of rows in a textbox?
Apr 24, 2008 12:02 PM|auztin100|LINK
1) Yes, didn't spot that one, as I am playing with it, there are other problems
Not sure what you mean about the onclick ... try taking out the section of the script regarding function---below---
function addLoadEvent(func) {
var oldonload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
} else {
window.onload = function() {
if (oldonload) {
oldonload();
}
func();
}
}
}
addLoadEvent(
function () {
document.amada.subjects.onkeyup = function () {
cleanUpList(document.amada.subjects);
}
}
);
Another problem I found is that if you are using word wrap, the lines a re not counted, but all as 1 line, so you get halfway along the next line and it prevents entering anymore text, until you CR !
I still looking for a solution to this, and have been for 2 days ! it is more of a javascript thing, than an ASP though....
Member
93 Points
592 Posts
Re: How do you limit number of rows in a textbox?
Apr 28, 2008 04:34 AM|swaino|LINK
Ok, give me an update if you can when you find a better solution. I'll try and investigate too...
Member
30 Points
41 Posts
Re: How do you limit number of rows in a textbox?
Oct 31, 2008 06:02 AM|jderonde|LINK
Hokies had the same problem with this with text box trying to pass to flash where the text apears for a print label. Managed to find a solution to this one let me know if it works for you ;)
<
script type="text/javascript">var alert_title='Input Restriction';
function limitTextarea(textarea,maxLines,maxChar)
{
var lines=textarea.value.replace(/\r/g,'').split('\n'),
lines_removed,
char_removed,
i;
if(maxLines&&lines.length>maxLines)
{
alert('You can not enter\nmore than '+maxLines+' lines');
lines=lines.slice(0,maxLines);
lines_removed=1
}
if(maxChar)
{
i=lines.length;
while(i-->0)if(lines[i].length>maxChar)
{
lines[i]=lines[i].slice(0,maxChar);
char_removed=1
}
if(char_removed)
{
alert('You can not enter more\nthan '+maxChar+' characters per line')
}
if(char_removed||lines_removed)
{
textarea.value=lines.join('\n')
}
function watchTextarea()
{
document.getElementById('resticted').onkeyup()
}
function set_ie_alert()
{
window.alert=function(msg_str)
{
vb_alert(msg_str)
}
}
}
}
</script>
<
textarea onkeyup="limitTextarea(this,6,40)" onfocus="focus_watch=setInterval('watchTextarea()',250)" onblur="clearInterval(focus_watch)">some text</textarea>Hokies sorry about the messy code and you will have to remove the alerts as they are tackey and you wouldnt want your user to see them i just used them for testing purposes.
Hope this helps
joe