在Swift中有条件的麻烦

Question

我被困在以下问题集上。有什么想法吗？

var hasFuel == "true"

if hasFuel == "true" {
    print("Let's go for a drive")
} else if hasFuel != "true" {
    print("We're not going anywhere!")
}

Answer 1

这是赋值运算符与相等运算符的错误。

代码无法编译

  

'=='不是前缀一元运算符

您可能想分配该值

var hasFuel = "true"

更好

var hasFuel = true

这避免了第二个if

if hasFuel == true {
    print("Let's go for a drive")
} else {
    print("We're not going anywhere!")
}

或更短

if hasFuel {
    print("Let's go for a drive")
} else {
    print("We're not going anywhere!")
}