我在这里有一个非常奇怪的错误,我搜索了周围,我已经尝试了所有的建议.没有工作
scrollView.contentSize.height = 325 * globals.defaults.integer(forKey: "numCards")
Binary operator ‘*’ cannot be applied to two ‘Int’ operands
WTF Swift!为什么不?我一直乘以Ints.这些是两个Ints. globals.defaults只是UserDefaults.standard的一个实例.我每次尝试以下相同的错误.
325 * Int(globals.defaults.integer(forKey: "numCards") //NOPE Int(325) * Int(globals.defaults.integer(forKey: "numCards")) //NOPE if let h = globals.defaults.integer(forKey: "numCards"){ 325 * h //NOPE,and 'Initializer for conditional binding must have optional type,not Int' } let h = globals.defaults.integer(forKey: "numCards") as! Int 325 * h //NOPE,and 'Forced cast of Int of same type as no affect' 325 * 2 //YES! But no shit...
所有这些“尝试”似乎都是浪费时间,因为我知道这两个都是Ints …而且我是正确的.请指教.谢谢!
错误是误导性的.该问题实际上是试图将一个Int值分配给一个CGFloat变量.
原文链接:https://www.f2er.com/swift/318775.html这将工作:
scrollView.contentSize.height = CGFloat(325 * globals.defaults.integer(forKey: "numCards"))
导致误导性错误的原因(感谢Daniel Hall在下面的评论中)是由于编译器选择返回CGFloat的*函数,因为需要返回值.这个相同的功能需要两个CGFloat参数.由于提供的两个参数是Int而不是CGFloat,所以编译器提供了误导性的错误:
Binary operator ‘*’ cannot be applied to two ‘Int’ operands
如果错误更像:
Binary operator ‘*’ cannot be applied to two ‘Int’ operands. Expecting two ‘CGFloat’ operands.