你的代码不需额外编译首先,你得到的错误error: variable 'filter' used before being initialized
所以声明过滤器如下: var filter = String()
或var filter = ""
其次,因为you're不添加所有的代码,我的试过如下:
var filter = String()
let x = 0
switch x {
case 1:
print("1")
default:
filter = "value"
print(filter)
}
print(filter)
此打印出:
value
value
如果您需要更多帮助,请通过更多信息更新您的问题。
更新:
只是想你更新的代码: VAR过滤=字符串() 让论据= “QWE”, “价值”, “QWE”, “ASD”] 打印(arguments.count ) 开关arguments.count { 壳体1: 断裂 壳体2: 断裂 壳体3: 滤波器=参数[1]
default:
filter = arguments[1]
print (filter)
}
print (filter)
这打印出来:
4
value
value
这正是它应该打印出来。请记住filter
的初始化。
更新2:
这是you're试图做的,你的其他结果总是返回4,因为that's的arguments
计数。改为尝试下面的代码。
var filter = String()
func Usage() {
print("Usage: <filter> <input> [output]")
print("System filter paths do not need to be specified.")
return
}
let arguments = ["qwe", "value", "qwe", "asd"]
print(arguments.count)
for i in 0..<arguments.count {
switch i {
case 0:
Usage()
case 1:
Usage()
case 2:
Usage()
case 3:
filter = arguments[1]
default:
filter = arguments[1]
print (filter)
}
}
print (filter)
此打印出:
4
Usage: <filter> <input> [output]
System filter paths do not need to be specified.
Usage: <filter> <input> [output]
System filter paths do not need to be specified.
Usage: <filter> <input> [output]
System filter paths do not need to be specified.
value
switch
在filter
请更新与足够的代码你的问题,为人们重现该问题。这并不意味着你的整个项目。 – rmaddy嗨benwiggy,这是不足以重现问题的代码。 – Arrabidas92