A div that does not overflow - css

Question

I have a div that will hold some text. The width of the div is fixed in pixels. I want to make sure that if the text takes more space than one line in the div, the text does not overflow and does not wrap to a second line. I just want it to show as much as fits the width of the div on one line. I have been experimenting with
{
overflow:hidden;
height:1em;
width:160px;
}
and it sometimes works, but I don't have the right height. What would be the right height? There is probably a better way to do this. Please let me know. Thanks!
Thanks everyone for your contributions. Here is what worked for me:
for a div:
{
height:1.2em;
text-overflow:ellipsis;
overflow:hidden;
white-space:nowrap;
}
note that both text-overflow:ellipsis; and white-space:nowrap; need to be there for the ellipsis to show.
And for a span note that spans don't have a width so you need to add:
{
display:inline-block;
width:160px;
}
for spans to work

Answer 1

overflow:hidden;
height:1em;
width:160px;
text-overflow: ellipsis;
line-height: 1em;
Will add an ellipsis to text if it overflows the enclosing div and set the div to only use 1em, the height of the container.

Answer 2

white-space: no-wrap will prevent a wrap of the text.

Answer 3

{
white-space:nowrap;
overflow:hidden;
height:1em;
width:160px;
}

Answer 4

Set the line height for the paragraph, then set the div height to be the same.
Just note that text is usually taller than 1 em, 1.3 or 1.4 is usually better.
Try it out here: http://jsfiddle.net/PYA3y/
#mydiv{
overflow:hidden;
height:1.4em;
width:160px;
}
#mydiv p{line-height:1.4em;}
Edit:
in the time I wrote my reply, you got 3 other answers!
Scott had a good idea for using the ellipsis, I've updated the JSFiddle to include it (although it doesn't work??)
If I understand correctly, setting white-space will not give you the result you require... you do want the extra text to be hidden, don't you?