Question

在official swift document中说＆＃34; print(_:separator:terminator:)函数是一个全局函数，可以将一个或更多值打印到适当的输出。＆＃34;

var welcomeMessage = "Hello"
var friendlyWelcom = "Hello!"

print(friendlyWelcom, separator: ",", terminator: "", welcomeMessage, separator: ",", terminator: "") // Why this is not working

问题作为代码中的注释 - 为什么print(friendlyWelcom, welcomeMessage)和print(friendlyWelcom, separator: ",", terminator: ""有效但print(friendlyWelcom, separator: ",", terminator: "", welcomeMessage, separator: ",", terminator: "")会产生编译错误？

Answer 1

您不能简单地添加命名参数。相反，您应该将变量传递给以逗号分隔的第一个参数。然后它们与中间的分隔符和末尾的终结符连接：

print(friendlyWelcom, welcomeMessage, separator: " - ", terminator: "?")

输出

您好！ - 您好？

您可以根据需要添加任意数量的变量：

print(friendlyWelcom, welcomeMessage, 123, "somethingElse", "etc", separator: " - ", terminator: "!!!!")

您好！ - 你好 - 123 - somethingElse - etc !!!!

尝试打印两个值时出错

1 个答案: