Reports say that the actress has agreed to marry the Annie Automatic rocker after he proposed on Thursday (August 8).
High School Musical star Ashley is said to be over the moon after the musician proposed to her on top of the Empire State Building in New York.
Ashley, 28, sent an excited tweet out just hours later, which could be seen to confirm the reports.
She wrote: "Best night of my life. We're on top of the world."
Best night of my life. We're on top of the world— Ashley Tisdale (@ashleytisdale) August 9, 2013
Ashley has also been seen wearing two rings on her left engagement finger.
According to Life & Style magazine, Christopher's romantic proposal swept Ashley off her feet.
A source said: "It happened on the 103rd floor at the top of the Empire State Building.
"It was totally romantic and Ashley's over the moon, of course!"
If the news is true, it's turning out to be an exciting year for Ashley, who will be starring as Nicolas Cage's daughter in upcoming film Left Behind.
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