trouble with getElementsByTagName

azstyx · 03-23-2005, 03:43 PM

hello Team,
I was trying to use the getElementsByTagName to list all the tables and forms in a document....however it appears that the result of the table elements is just "undefined". What am I doing wrong?
thx!!

=====
htlm/js code
=======
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>JS Forms Play</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<script language="JavaScript1.2" type="text/JavaScript">

</script>
</head>
<body>
<table width="300" border="1" cellspacing="0" cellpadding="0" ID=T1>
<tr>
<th>Table#1 Header</th>
</tr>
<td>example table line</td></tr>
</TABLE>
<br>
<table width="300" border="1" cellspacing="0" cellpadding="0" ID=T2>
<tr>
<th>Table#2 Header</th>
</tr>
<td>example table line2</td></tr>
</TABLE>
<h1>Form Test</h1>
<FORM action="" method="GET" name="myForm" id="myForm" >
My Name: <input name="frm_name" type="text" id="frm_name" value="Example Name" size="40" maxlength="40">
<br>
checkbox1: <input type=checkbox name="cb1" id="cb1" value=11><br>
checkbox2: <input type=checkbox name="cb2" id="cb2" value=22><br>
checkbox3: <input type=checkbox name="cb3" id="cb3" value=33><br>
<input type="BUTTON" name="btnall" id="btnall" value="Check All"
onClick="setAll();"><br>
<input type="BUTTON" name="btnobjects" id="btnobjects" value="List Objects"
onClick="listObjects();"><br>
<input type="SUBMIT" name="frmSubmit" id="frmSubmit" value="Submit">
<input type="RESET" name="frmReset" id="frmReset" value="Reset">
</FORM>
</body>
</html>

======
Results when I click on List Objects button:
================

Num of tables found: 2
Num of forms found: 1
Table List:
TableName=>undefined
TableName=>undefined
Form List:
FormName=>undefined

afru · 03-23-2005, 06:12 PM

Checkout this code...

Code:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>JS Forms Play</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<script language="JavaScript1.2" type="text/JavaScript">
<!--
function listObjects() {
var myTables = document.getElementsByTagName("TABLE");
var myForms = document.getElementsByTagName("FORM");
var myTableslen = myTables.length;
var myFormslen = myForms.length;
var name;
alert("Num of tables found: "+myTableslen);
alert("Num of forms found: "+myFormslen);
alert("Table List :");
for (x=0; x<myTableslen; x++) {
alert("TableName=>"+myTables[x].id);
}
alert("Form List :");
for (x=0; x<myFormslen; x++) {
alert("FormName=>"+myForms[x].id);
}

}
function setAll() {

}
// -->
</script>
</head>
<body>
<table width="300" border="1" cellspacing="0" cellpadding="0" id="T1">
<tr>
<th>Table#1 Header</th>
</tr>
<td>example table line</td></tr>
</TABLE>
<br>
<table width="300" border="1" cellspacing="0" cellpadding="0" id="T2">
<tr>
<th>Table#2 Header</th>
</tr>
<td>example table line2</td></tr>
</TABLE>
<h1>Form Test</h1>
<FORM action="" method="GET" name="myForm" id="myForm" >
My Name: <input name="frm_name" type="text" id="frm_name" value="Example Name" size="40" maxlength="40">
<br>
checkbox1: <input type=checkbox name="cb1" id="cb1" value=11><br>
checkbox2: <input type=checkbox name="cb2" id="cb2" value=22><br>
checkbox3: <input type=checkbox name="cb3" id="cb3" value=33><br>
<input type="BUTTON" name="btnall" id="btnall" value="Check All"
onClick="setAll();"><br>
<input type="BUTTON" name="btnobjects" id="btnobjects" value="List Objects"
onClick="listObjects();"><br>
<input type="SUBMIT" name="frmSubmit" id="frmSubmit" value="Submit">
<input type="RESET" name="frmReset" id="frmReset" value="Reset">
</FORM> 
</body>
</html>

azstyx · 03-23-2005, 07:27 PM

Cool!!! I see now why my document.writeln did not work and I kept getting undefined and object does not exist. When i used the writeln it overwrote my current window destroying my previous objects such as tables for the form. I have include a window.open now:
var auxwin = window.open("","auxwindow");

I updated my writeln to reference the new window for writing to:
auxwin.document.writeln("TableName=>"+name+"<br>");

Now it's working.....THANKS!!
Styx