asked on

TextChanged event not working

I want to check the length of letters in the textbox. If the length equals 7 then I want to shift the focus to the next textbox control.

I have added the following in the textboxchanged event

Private Sub txtSaleItem_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtSaleItem.TextChanged
If Len(txtSaleItem.Text) = 7 Then
Call SetFocus.set_focus(Me, txtSaleQty)
End If
End Sub

Public Class SetFocus
Public Shared Sub set_focus(ByRef p_page As System.Web.UI.Page, ByVal p_control As System.Web.UI.Control)
Dim w_str As String
If Not (p_control Is Nothing) Then
w_str = "<script language=JavaScript>document.forms(0).elements['" & p_control.ClientID().ToString() & "'].focus();</script>"
p_page.Controls.Add(New System.Web.UI.LiteralControl(w_str))
End If
End Sub
End Class

I have set the textbox Autopostback property to TRUE.

The event is firing when the textbox loses focus but I want it to fire as the the user enters the letters and check for the length of text in the textbox.

Help would be appreciated.
Thanks

dgelinas

Sounds to me like you would only be able to do that using Javascript.

In javascript you can write a function that will check the length of the field value from the onkeyup property of the field. Test the below working code.

<html>
<head>
</head>

<body>
<script>
function check(field) {
if(field.value.length==7){
document.forms[0].field2.focus();
}
}
</script>

<form id="form1">
<input name="field1" type="text" onkeyup="check(this)">
<br>
<br>
<input name="field2" type="text">
<br>
<br>
</form>

</body>
</html>

wilkersons

ASKER

Well, I am user the textbox server control and it does not have keyup or keydown events...so where should I use the

check(this) function??

dgelinas

<%@ Page Language="C#" ContentType="text/html" ResponseEncoding="iso-8859-1" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Untitled Document</title>
</head>
<body>
<script>
function check(field) {
if(field.value.length==7){
document.forms[0].field2.focus();
}
}
</script>
<form runat="server">
<asp:Textbox id="field1" runat="server" OnKeyUp="check(this)"></asp:Textbox>
<asp:Textbox id="field2" runat="server"></asp:Textbox>
</form>

</body>
</html>

wilkersons

ASKER

<asp:Textbox id="txtSaleItem" runat="server" OnKeyUp="check(this)"></asp:Textbox>

Gives me an error at OnKeyUp (This is not an attribute for the element)

I tried the following:

txtSaleItem.Attributes.Add("onKeyUp", "Javascript:document.forms[0].item[txtSaleQty].focus();")

I need to move the focus to
<asp:Textbox id="txtSaleQty" runat="server" ></asp:Textbox>

I get an error as soon as I type the first letter in the txtSaleItem. This means that the onKeyUp does fire but I guess there is some syntax error at the javascript statement

The error is:
document.forms[0].item[....] is null or not an object

Can you suggest something??
Thanks

ASKER CERTIFIED SOLUTION

dgelinas

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wilkersons

ASKER

I tried
txtSaleItem.Attributes.Add("onKeyUp", "Javascript:if (document.forms[0].txtSaleItem.value.length==7){document.forms[0].txtSaleQty.focus();}")

and it is working !!!

Thanks for your help

dgelinas

No problem :)