Go 编程实例【运行时检查变量类型】

素颜马尾好姑娘i 2023-10-09 21:04 24阅读 0赞

#### 阅读目录 ####

*  示例
 *  示例1

## 示例 ##

package main
    
    import (
    	"fmt"
    	"reflect"
    )
    
    type Person struct {
        
    	Name string
    	Age  int
    }
    
    func typeofObject(variable interface{
        }) string {
        
    	switch variable.(type) {
        
    	case int:
    		return "int"
    	case float32:
    		return "float32"
    	case bool:
    		return "boolean"
    	case string:
    		return "string"
    	default:
    		// 如果是结构体类型，返回结构体名称
    		v := reflect.ValueOf(variable)
    		if v.Kind() == reflect.Struct {
        
    			return v.Type().Name() + " struct{}"
    		}
    		return "unknown"
    	}
    }
    
    func main() {
        
    	var a int = 42
    	var b float32 = 3.14
    	var c bool = true
    	var d string = "hello"
    	var e Person = Person{
        "John Doe", 30}
    
    	fmt.Println(typeofObject(a)) // Output: int
    	fmt.Println(typeofObject(b)) // Output: float32
    	fmt.Println(typeofObject(c)) // Output: boolean
    	fmt.Println(typeofObject(d)) // Output: string
    	fmt.Println(typeofObject(e)) // Output: Person
    }

root@debiancc:~/www/test# go run test.go 
    int
    float32
    boolean
    string
    Person struct{}
    root@debiancc:~/www/test#

## 示例1 ##

package main
    
    import "fmt"
    
    type Data struct {
        
    }
    
    func demo2(d Data) {
        
    	fmt.Println(typeofObject(d))
    }
    
    func demo1(v interface{
        }) {
        
    	//断言v为Data类型
    	demo2(v.(Data))
    }
    
    func main() {
        
    	//Data类型隐式转换成interface{}类型
    	demo1(Data{
        })
    }
    
    func typeofObject(variable interface{
        }) string {
        
    	switch variable.(type) {
        
    	case int:
    		return "int"
    	case float32:
    		return "float32"
    	case bool:
    		return "boolean"
    	case string:
    		return "string"
    	case struct{
        }:
    		return "struct{}"
    	case interface{
        }:
    		return "interface{}"
    	default:
    		return "unknown"
    	}
    }

root@debiancc:~/www/test# go run test.go 
    interface{}
    root@debiancc:~/www/test#