How could I write a function to print a map object in Go (Golang)? Right now I have this, but it doesn't compile. It returns cannot convert value (type interface {}) to type reflect.Kind: need type assertion.

package main

type MyDictionary map[string]interface{}

func (d MyDictionary) String() string {
    var stringBuffer bytes.Buffer

    for key, value := range d {
        stringBuffer.WriteString(key)
        stringBuffer.WriteString(": ")

        valueType := reflect.Kind(value)

        switch valueType {
        case reflect.String:
            log.Println("string") // just to check if this block gets executed
            // Add to stringBuffer

        case reflect.Float64:
            log.Println("float64") // just to check if this block gets executed
            // Add to stringBuffer

        default:
            log.Println("Error: type was", valueType)
        }
    }

    return stringBuffer.String()
}

func main() {
    var dict MyDictionary = make(MyDictionary)
    dict["hello"] = "world"
    dict["floating"] = 10.0
    dict["whole"] = 12

    fmt.Println(dict)
}

I want String() to return a string like hello: world floating: 10.0 whole: 12. That I can then pass to fmt.Println() to print this. In Java, I would use StringBuilder for this.

hello: world
floating: 10.0
whole: 12

I also tried switching on value.(type) with case string: and case float64, but then I didn't know how to write those values to stringBuffer.

string。StringBuilder。StringBuffer的相关问题

TomasHawking

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