Go问题

1.导出csv

go导出CSV中字符串带有英文逗号，只需要在字符串两端加上"\""
https://www.cnblogs.com/softidea/p/5313516.html

2.go 转json的问题

1、slice 的话需要&
var getOrderSlice []*TempOrder
err = json.Unmarshal([]byte(orderData), &getOrderSlice)
2、struct 的话不需要&
coun := &Guider{}
err = json.Unmarshal([]byte(nc), coun)

3.引入包需要引入的是文件夹名称而不是包名

rrdEsExport "git.twxrrd.com/wh.tech.rrd/daemon.jobs/model/wxrrd.ex.export"
不是
rrdEsExport "git.twxrrd.com/wh.tech.rrd/daemon.jobs/model/rrd_es_export"
package rrd_es_export

4.字符串拼接方法

1、+号拼接
func StringPlus() string{
    var s string
    s+="昵称"+":"+"飞雪无情"+"\n"
    s+="博客"+":"+"http://www.flysnow.org/"+"\n"
    s+="微信公众号"+":"+"flysnow_org"
    return s
}
2、fmt 拼接
func StringFmt() string{
    return fmt.Sprint("昵称",":","飞雪无情","\n","博客",":","http://www.flysnow.org/","\n","微信公众号",":","flysnow_org")
}
3、Join 拼接
func StringJoin() string{
    s:=[]string{"昵称",":","飞雪无情","\n","博客",":","http://www.flysnow.org/","\n","微信公众号",":","flysnow_org"}
    return strings.Join(s,"")
}
4、buffer 拼接
func StringBuffer() string {
    var b bytes.Buffer
    b.WriteString("昵称")
    b.WriteString(":")
    b.WriteString("飞雪无情")
    b.WriteString("\n")
    b.WriteString("博客")
    b.WriteString(":")
    b.WriteString("http://www.flysnow.org/")
    b.WriteString("\n")
    b.WriteString("微信公众号")
    b.WriteString(":")
    b.WriteString("flysnow_org")
    return b.String()
}
5、builder 拼接
func StringBuilder() string {
    var b strings.Builder
    b.WriteString("昵称")
    b.WriteString(":")
    b.WriteString("飞雪无情")
    b.WriteString("\n")
    b.WriteString("博客")
    b.WriteString(":")
    b.WriteString("http://www.flysnow.org/")
    b.WriteString("\n")
    b.WriteString("微信公众号")
    b.WriteString(":")
    b.WriteString("flysnow_org")
    return b.String()
}

str:="chinese"
    city:="beijing"
    
    // 1. +=
    s:=time.Now()
    for i:=0;i<100000;i++ {
        str +=city
    }
    e:=time.Since(s)
    fmt.Println("time cost 1:", e)
  
    // 2. fmt.Sprintf
    str="chinese"
    city="beijing"
    s=time.Now()
    for i:=0;i<100000;i++ {
        str = fmt.Sprintf("%s%s",str,city)
    }
    e=time.Since(s)
    fmt.Println("time cost 2:", e)
  
     //3.  buffer.WriteString
    str="chinese"
    city="beijing"
    s=time.Now()
    var buf= bytes.Buffer{}
    buf.WriteString(str)
    for i:=0;i<100000;i++ {
        buf.WriteString(city)
    }
    e=time.Since(s)
    fmt.Println("time cost 3:", e)

   //4. append
    str="chinese"
    city="beijing"
    s=time.Now()
    bstr:=[]byte(str)
    bcity:=[]byte(city)
    for i:=0;i<100000;i++ {
        bstr= append(bstr, bcity...)
    }
    e=time.Since(s)
    fmt.Println("time cost 4:", e)

  // 5. copy
    str="chinese"
    city="beijing"
    s=time.Now()
    zstr :=[]byte(str)
    for i:=0;i<100000;i++ {
        copy(zstr, city)
    }
    e=time.Since(s)
    fmt.Println("time cost 5:", e)
    
    time cost 1: 3.176250251s
    time cost 2: 5.347827717s
    time cost 3: 1.051104ms
    time cost 4: 769.258µs
    time cost 5: 323.968µs

5. gin框架PostForm

1. 获取 Content-Type:application/x-www-form-urlencoded

接收参数

orderNo := c.PostForm("order_no")

post请求

## request.Header.Set("Content-Type", "application/x-www-form-urlencoded")

func CurlPostStringData(stringData string, url string) ([]byte, error) {
    //body := strings.NewReader("order_no=cjb&name=xiao")
    body := strings.NewReader(stringData)
    request, err := http.NewRequest("POST", url, body)
    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,http NewRequest error is %v", url, stringData, err)
        return nil, err
    }
    request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
    //使用连接池httpClient
    httpClient := &http.Client{}
    httpClient.Transport = &http.Transport{
        Proxy: http.ProxyFromEnvironment,
        DialContext: (&net.Dialer{
            Timeout:   30 * time.Second,
            KeepAlive: 30 * time.Second,
            DualStack: true,
        }).DialContext,
        MaxIdleConns:          100,
        MaxIdleConnsPerHost:   100,
        IdleConnTimeout:       90 * time.Second,
        TLSHandshakeTimeout:   90 * time.Second,
        ExpectContinueTimeout: 1 * time.Second,
    }

    resp, err := httpClient.Do(request)
    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,client Do request error is %v", url, string(stringData), err)
        return nil, err
    }
    respBytes, err := ioutil.ReadAll(resp.Body)
    log.WithChannel("222").Printf("%s",string(respBytes))

    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,result ioutil ReadAll error is %v", url, string(stringData), err)
        return nil, err
    }
    return respBytes, nil
}

2. 获取Content-Type:application/json;charset=UTF-8

接收参数

type TestS struct {
    OrderNo string `json:"order_no"`
    Name string `json:"name"`
}

func Register(c *gin.Context) {
    body, _ := ioutil.ReadAll(c.Request.Body) //josn数据
    test := &TestS{}
    _=json.Unmarshal(body,test)
}

post请求

## request.Header.Set("Content-Type", "application/json;charset=UTF-8")

func CurlPost(byteData []byte, url string) ([]byte, error) {
    //body := strings.NewReader("order_no=cjb&name=xiao")
    body := bytes.NewReader(byteData)
    request, err := http.NewRequest("POST", url, body)
    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,http NewRequest error is %v", url, string(byteData), err)
        return nil, err
    }
    request.Header.Set("Content-Type", "application/json;charset=UTF-8")

    //使用连接池httpClient
    httpClient := &http.Client{}
    httpClient.Transport = &http.Transport{
        Proxy: http.ProxyFromEnvironment,
        DialContext: (&net.Dialer{
            Timeout:   30 * time.Second,
            KeepAlive: 30 * time.Second,
            DualStack: true,
        }).DialContext,
        MaxIdleConns:          100,
        MaxIdleConnsPerHost:   100,
        IdleConnTimeout:       90 * time.Second,
        TLSHandshakeTimeout:   90 * time.Second,
        ExpectContinueTimeout: 1 * time.Second,
    }

    resp, err := httpClient.Do(request)
    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,client Do request error is %v", url, string(byteData), err)
        return nil, err
    }
    respBytes, err := ioutil.ReadAll(resp.Body)
    log.WithChannel("222").Printf("%s",string(respBytes))

    if err != nil {
        log.WithChannel("curl post").Printf("url=%s,data=%s,result ioutil ReadAll error is %v", url, string(byteData), err)
        return nil, err
    }
    return respBytes, nil
}