golang基础-json序列化、反序列化、自定义error

json协议

结构体转json

package mainimport (    "fmt"    "encoding/json")type User struct {    UserName string `json:"username"`    NickName string `json:"nickname"`    Age      int    Birthday string    Sex      string    Email    string    Phone    string}/*结构体转json*/func testStruct() {    user1 := &User{        UserName: "user1",        NickName: "上课看似",        Age:      18,        Birthday: "2008/8/8",        Sex:      "男",        Email:    "[e-mail]",        Phone:    "110",    }    data, err := json.Marshal(user1)    if err != nil {        fmt.Printf("json.marshal failed, err:", err)        return    }    fmt.Printf("%s\n", string(data))}func main() {    testStruct()    fmt.Println("----")}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.go{"username":"user1","nickname":"上课看似","Age":18,"Birthday":"2008/8/8","Sex":"男","Email":"[e-mail]","Phone":"110"}----PS E:\golang\go_pro\src\safly>

map转json

package mainimport (    "fmt"    "encoding/json")type User struct {    UserName string `json:"username"`    NickName string `json:"nickname"`    Age      int    Birthday string    Sex      string    Email    string    Phone    string}/*map转json*/func testMap() {    var mmp  map[string]interface{}    mmp = make(map[string]interface{})    mmp["username"] = "user"    mmp["age"] = 19    mmp["sex"] = "man"    data,err := json.Marshal(mmp)    if err != nil{        fmt.Println("json marshal failed,err:",err)        return    }    fmt.Println("%s\n",string(data))}func main() {    testMap()    fmt.Println("----")}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.go{"age":19,"sex":"man","username":"user"}----PS E:\golang\go_pro\src\safly>

int转json

package mainimport (    "fmt"    "encoding/json")type User struct {    UserName string `json:"username"`    NickName string `json:"nickname"`    Age      int    Birthday string    Sex      string    Email    string    Phone    string}/*slice转json*/func testSlice() {}func testInt() {    var age = 100    data, err := json.Marshal(age)    if err != nil {        fmt.Printf("json.marshal failed, err:", err)        return    }    fmt.Printf("%s\n", string(data))}func main() {    testSlice()    testInt()    fmt.Println("----")}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.go100----PS E:\golang\go_pro\src\safly>

slice转json

package mainimport (    "fmt"    "encoding/json")func testSlice() {    var m map[string]interface{}    var s []map[string]interface{}    m = make(map[string]interface{})    m["username"] = "user1"    m["age"] = 18    m["sex"] = "man"    s = append(s, m)    m = make(map[string]interface{})    m["username"] = "user2"    m["age"] = 29    m["sex"] = "female"    s = append(s, m)    data, err := json.Marshal(s)    if err != nil {        fmt.Printf("json.marshal failed, err:", err)        return    }    fmt.Printf("%s\n", string(data))}func main() {    testSlice()}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.go[{"age":18,"sex":"man","username":"user1"},{"age":29,"sex":"female","username":"user2"}]PS E:\golang\go_pro\src\safly>

json反序列化为结构体

package mainimport (    "encoding/json"    "fmt")type User struct {    UserName string `json:"username"`    NickName string `json:"nickname"`    Age      int    Birthday string    Sex      string    Email    string    Phone    string}func testStruct() (ret string, err error) {    user1 := &User{        UserName: "user1",        NickName: "上课看似",        Age:      18,        Birthday: "2008/8/8",        Sex:      "男",        Email:    "[e-mail]",        Phone:    "110",    }    data, err := json.Marshal(user1)    if err != nil {        err = fmt.Errorf("json.marshal failed, err:", err)        return    }    ret = string(data)    return}func test() {    data, err := testStruct()    if err != nil {        fmt.Println("test struct failed, ", err)        return    }    var user1 User    err = json.Unmarshal([]byte(data), &user1)    if err != nil {        fmt.Println("Unmarshal failed, ", err)        return    }    fmt.Println(user1)}func main() {    test()    // test2()}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.go{user1 上课看似 18 2008/8/8 男 [e-mail] 110}PS E:\golang\go_pro\src\safly>

json反序列化为map

package mainimport (    "encoding/json"    "fmt")func testMap() (ret string, err error) {    var m map[string]interface{}    m = make(map[string]interface{})    m["username"] = "user1"    m["age"] = 18    m["sex"] = "man"    data, err := json.Marshal(m)    if err != nil {        err = fmt.Errorf("json.marshal failed, err:", err)        return    }    ret = string(data)    return}func test2() {    data, err := testMap()    if err != nil {        fmt.Println("test map failed, ", err)        return    }    var m map[string]interface{}    err = json.Unmarshal([]byte(data), &m)    if err != nil {        fmt.Println("Unmarshal failed, ", err)        return    }    fmt.Println(m)}func main() {    test2()}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.gomap[age:18 sex:man username:user1]PS E:\golang\go_pro\src\safly>

自定义error

package mainimport (    "fmt"    "os"    "time")type PathError struct {    path       string    op         string    createTime string    message    string}func (p *PathError) Error() string {    return fmt.Sprintf("path=%s op=%s createTime=%s message=%s", p.path,        p.op, p.createTime, p.message)}/*type error interface {    Error() string}*/func Open(filename string) error {    file, err := os.Open(filename)    if err != nil {        return &PathError{            path:       filename,            op:         "read",            message:    err.Error(),            createTime: fmt.Sprintf("%v", time.Now()),        }    }    defer file.Close()    return nil}func main() {    err := Open("C:/sdklflakfljdsafjs.txt")    switch v := err.(type) {    case *PathError:        fmt.Println("get path error,", v)    default:    }}

输出如下：

PS E:\golang\go_pro\src\safly> go run demo.goget path error, path=C:/sdklflakfljdsafjs.txt op=read createTime=2017-11-05 20:09:23.4928719 +0800 CST message=open C:/sdklflakfljdsafjs.txt: The system cannot find the file specified.PS E:\golang\go_pro\src\safly>