disabeling enters in textarea

[ShMiL]

I want to replace the enters (break lines) with a blank space when the user press the "enter" button on the <textarea>.
Any idea?

[glenngv]

why not just use a normal text field? Textarea is a multi-line text field, why would you change that?

[ShMiL]

Because I have to. I want the user to see all that he writes (100 chars). Normal text field won't do.

[glenngv]

then set the size to 100

<input type="text" name="txt" size="100">

[ShMiL]

come on...
Leave the design part to me - I have a JS issue here, don't teach me HTM.
Anyone has any idea?