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trying to check for blanks in textbox using javascript

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duckyboyz

duckyboyz

Programmer
Mar 28, 2002
57
US
i'm using the following code to try to check for blanks in textbox1 (lastname):

<%@ Page Language="VB" %>
<script runat="server">

' Insert page code here
'

Sub Button1_Click(sender As Object, e As EventArgs)
response.redirect("homeApp.aspx")
End Sub

</script>
<html>
<head>
<script language="JavaScript">

function validatePage(sender, args)
{
if (document.getElementById("textbox1").value.length < 2)
{
args.IsValid = false;
return false;
}
else
{
args.IsValid = true;
return true;
}

}

</script>
</head>
<body>
<form id="form1" runat="server">
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
</p>
<p>
<asp:Label id="Label1" runat="server">Label</asp:Label>&nbsp;&nbsp;&nbsp;&nbsp;
<asp:TextBox id="TextBox1" runat="server"></asp:TextBox>
<asp:CustomValidator id="CustomValidator1" runat="server" ErrorMessage="CustomValidator" ControlToValidate="TextBox1" ClientValidationFunction="validatePage"></asp:CustomValidator>
</p>
<p>
</p>
<p>
<asp:Label id="Label2" runat="server">something 2</asp:Label>&nbsp;&nbsp;
<asp:TextBox id="TextBox2" runat="server"></asp:TextBox>
</p>
<p>
</p>
<p>
<asp:Button id="Button1" onclick="Button1_Click" runat="server" Text="home"></asp:Button>
</p>
<p>
<!-- Insert content here -->
</p>
</form>
</body>
</html>
i can use "document.getElementById("textbox1").value.length < 2)" to check for atleast one char in the textbox, but < 0 does'nt work for no chars in the textbox1 field.

how do you check for blanks?

Mike Johnson
 
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Why don't you use a RequiredFieldValidator?


____________________________________________________________

Need help finding an answer?

Try the Search Facility or read FAQ222-2244 on how to get better results.

 
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If you are searching for blanks within a textbox then a customvalidator is what you need.

If you are trying to ensure that something has been entered then the RequiredFieldValidator is what you want.
 
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Microsoft said:
Extra spaces at the beginning and end of the input value are removed before validation is performed. This prevents a space being entered in the input control from passing validation.
Click to expand...
The RequiredFieldValidator already does this so you don't need to use a CustomValidator.


____________________________________________________________

Need help finding an answer?

Try the Search Facility or read FAQ222-2244 on how to get better results.

 
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I do know that, I was trying to explain that if he were looking for blanks (spaces) within a textbox then a customvalidator is what he would need.

Maybe a field with login that shouldn't have spaces, like:

"joewilliams" not "joe williams"

I over analyzed the question.
 
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no... it was requested that all validation be client-side, i.e. javascript.

Mike Johnson
 
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i use this RegExp
Code: 
function checktext(thefieldname,s) {
  var thefield = document.getElementById(thefieldname);
  var istxt = thefield.value;
  istxt = istxt.replace(/^\s+/,"").replace(/\s+$/,"").replace(/\s+/g," ");
  if(istxt != '') {
    return true;
  } else {
    if (s != '') { 
      alert(s);
    }
    thefield.focus();
    return false;
  } 
}

"...we both know I'm training to become a cagefighter...see what happens if you try 'n hit me..."
 
Upvote 0 Downvote
"no... it was requested that all validation be client-side, i.e. javascript."

The RequiredFieldValidator does perform validation on the client-side using javascript. It only works for IE in 1.x but I think they fixed the scripts in 2.0 for cross-browser compatibility.

If you try to do the validation your own way, you'll miss out on a lot of other snazzy validation framework features: it isn't recommended.
 
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