i had a beautiful dress as yours

The phrase "I had a beautiful dress as yours" suggests that the speaker once owned a dress that was similar in beauty to another person's dress. The use of "as yours" indicates a comparison between the two dresses.

In terms of meaning, the speaker is expressing nostalgia or a fond memory related to the dress they used to own. There's an implication that the dress the speaker had was equally beautiful, which can create a sense of connection or camaraderie with the person they're speaking to.

The past tense "had" shows that this dress is no longer in the speaker's possession, possibly due to a number of reasons—such as having given it away, it no longer fitting, or simply being a memory. This adds a layer of sentimentality to the statement, suggesting that the speaker might miss the dress or the experience associated with it.

Overall, the statement is both a compliment to the other person's dress while also being reflective about the speaker's own past.