Ios 在swift 3中输入参数
这是我的代码:Ios 在swift 3中输入参数,ios,swift,swift3,Ios,Swift,Swift3,这是我的代码: func removeFromString( _ s: inout String, Character c:Character) -> Int { var s1 = s var nRemoved = 0 while let ix = s1.characters.index(of: c) { s1.removeSubrange(ix...ix) nRemoved += 1 } return nRemo
func removeFromString( _ s: inout String, Character c:Character) -> Int {
var s1 = s
var nRemoved = 0
while let ix = s1.characters.index(of: c) {
s1.removeSubrange(ix...ix)
nRemoved += 1
}
return nRemoved
}
var s2 = "everest"
let resb = removeFromString(&s2, Character: Character("e"))
我的问题是,在使用
inout
参数s
后,应该将s2更改为“vrst”。但它根本没有修改var s2
。我做错了什么?或者我期望输出错误?一定要帮忙。谢谢。通过将s
移动到s1
中,您就是在复制它,因为字符串是一个结构,所有结构都是按值传递的。因此,最后您只更改了s1
,而不是传入的字符串s
。只需删除它:
func removeFromString( _ s: inout String, Character c:Character) -> Int {
var nRemoved = 0
while let ix = s.characters.index(of: c) {
s.removeSubrange(ix...ix)
nRemoved += 1
}
return nRemoved
}
完美的谢谢!:)更简单:
s.remove(at:ix)
。