how to echo this "&"

[tsuibin]

i write & on a button,
make ,but then i see it change to "_" or can't see it
why ? hot to solve it ?
some people said use &&,
who has a better way

[spirit]

from Qt Assistant

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On certain widgets, using '&' in front of a character will automatically create a mnemonic (a shortcut) for that character, e.g. "E&xit" will create the shortcut Alt+X (use '&&' to display an actual ampersand).
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read this for more info.