29.笔记go语言——函数多类型参数

29.笔记go语言——函数多类型参数
如果希望在函数中传任意类型，可以指定类型为interface{}。下面是Go语言标准库中fmt.Printf()的函数原型：

func Printf(format string, args...interface{}) {

 //... 

} 

用interface{}传递任意类型数据是Go语言的惯例用法。使用interface{}仍然是类型安全的，这和C/C++ 不太一样。

传入interface{}类型的数据。

代码：

package main

 

import "fmt"

 

func MyPrintf(args ...interface{}) {

                                        for_, arg := range args {

                                                                                switcharg.(type) {

                                                                                caseint:

                                                                                                                        fmt.Println(arg,"is an int value.")

                                                                                casestring:

                                                                                                                        fmt.Println(arg,"is a string value.")

                                                                                caseint64:

                                                                                                                        fmt.Println(arg,"is an int64 value.")

                                                                                default:

                                                                                                                        fmt.Println(arg,"is an unknown type.")

                                                                                }

                                        }

}

func main() {

                                        varv1 int = 1

                                        varv2 int64 = 234

                                        varv3 string = "hello"

                                        varv4 float32 = 1.234

                                        MyPrintf(v1,v2, v3, v4)

}

执行：

                                        1is an int value.

                                        234is an int64 value.

                                        hellois a string value.

                                        1.234is an unknown type.