Is there any way to determine whether a variable has properties?

[Ramon F Herrera]

Hello,

I have a table whose entries are not all defined. My current code
looks like this:

var shouldHide = noEarnings.isBoxChecked(0);

for (var i = 0; i < rows; i++)
for (var j = 0; j < 2; j++)
if ((i!=3 || j!=1) && (i!=4 || j !=1) && (i!=6 || j!=1)) //
<-- These are the undefined entries
amountTable[j].hidden = shouldHide;
else
console.println("Table " + (i+1) + ", " + (j+1) + " is
undefined");

Naturally, I would like to write more general code, checking whether
the entry exists before trying to [un]hide it.

TIA,

-Ramon

ps: This is JavaScript for Acrobat forms.

 

[Thomas 'PointedEars' Lahn]

var shouldHide = noEarnings.isBoxChecked(0);

for (var i = 0; i < rows; i++)
for (var j = 0; j < 2; j++)
if ((i!=3 || j!=1) && (i!=4 || j !=1) && (i!=6 || j!=1)) //
<-- These are the undefined entries
amountTable[j].hidden = shouldHide;
else
console.println("Table " + (i+1) + ", " + (j+1) + " is
undefined");

Naturally, I would like to write more general code, checking whether
the entry exists before trying to [un]hide it.

In the most simple but compact form:

for (...)
{
for (...)
{
var row = amountTable, cell;
if (row && (cell = row[j]))
{
cell.hidden = shouldHide;
}
}
}

RTFM, RTFFAQ, STFW.


PointedEars