今天看到問Swift問題: Initializer for conditional binding must have Optional type, not 'String'
以前沒遇到過這個問題,這不趕緊寫個demo驗證一下,弄懂什么問題吧,算是積累小知識了.
報錯原因:
if 里面的判斷類型必須是Optional類型。
解決方法:
注意不僅是if let會報錯,guard let 同樣是這樣...
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