golang post发送 json请求

实例1：

package main

import (
	"bytes"
	"fmt"
	"io/ioutil"
	"net/http"
)

func main() {
	url := "http://www.baidu.com"

	fmt.Println("url:>", url)

	usrId := "login"
	pwd := "pwd12344"

	//json序列化
	post := "{\"UserId\":\"" + usrId +
		"\",\"Password\":\"" + pwd +
		"\"}"

	fmt.Println(url, "post", post)


	var jsonStr = []byte(post)
	fmt.Println("jsonStr", jsonStr)
	fmt.Println("new_str", bytes.NewBuffer(jsonStr))


	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonStr))
	// req.Header.Set("X-Custom-Header", "myvalue")
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil{
		panic(err)
	}
	defer resp.Body.Close()

	fmt.Println("status", resp.Status)
	fmt.Println("response:", resp.Header)
	body, _ := ioutil.ReadAll(resp.Body)
	fmt.Println("response Body:", string(body))

}

实例2：

import (
    "net/http"
    "encoding/json"
    "fmt"
    "bytes"
    "io/ioutil"
    "unsafe"
)
 
type JsonPostSample struct {
 
}
 
func (this *JsonPostSample) SamplePost() {
    song := make(map[string]interface{})
    song["name"] = "李白"
    song["timelength"] = 128
    song["author"] = "李荣浩"
    bytesData, err := json.Marshal(song)
    if err != nil {
        fmt.Println(err.Error() )
        return
    }
    reader := bytes.NewReader(bytesData)
    url := "http://localhost/echo.php"
    request, err := http.NewRequest("POST", url, reader)
    if err != nil {
        fmt.Println(err.Error())
        return
    }
    request.Header.Set("Content-Type", "application/json;charset=UTF-8")
    client := http.Client{}
    resp, err := client.Do(request)
    if err != nil {
        fmt.Println(err.Error())
        return
    }
    respBytes, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        fmt.Println(err.Error())
        return
    }
    //byte数组直接转成string，优化内存
    str := (*string)(unsafe.Pointer(&respBytes))
    fmt.Println(*str)
}