Go语言的编程范式

package form

import (
    "encoding/gob"
    "reflect"
    "regexp"
    "time"
)

type FormData struct {
    Errors  map[string]error  `json:"-" xml:"-" form:"-"`
    Warning map[string]string `json"-" xml:"-" form: "-"`
    Checked bool              `json"-" xml:"-" form: "-"`
}

// Use that as an amonynous field for creating form.
type Form struct {
    Data *FormData
}

// Get Error
func (f *Form) Err(name string) error {
    if f.Data == nil {
        return nil
    }
    if f.Data.Errors == nil {
        return nil
    }
    return f.Data.Errors[name]
}

// Set Error
func (f *Form) SetErr(name string, err error) {
    if f.Data == nil {
        f.Data = &FormData{}
    }
    if f.Data.Errors == nil {
        f.Data.Errors = map[string]error{}
    }
    f.Data.Errors[name] = err
}

// Has at least one Error
func (f *Form) HasErr() bool {
    if f.Data == nil {
        return false
    }
    return f.Data.Errors != nil
}

// Returns Error Format.
func (f *Form) ErrFormat() string {
    return `<p>%v</p>`
}

// Get Warning
func (f *Form) GetWarning(name string) string {
    if f.Data == nil {
        return ""
    }
    if f.Data.Warning == nil {
        return ""
    }
    return f.Data.Warning[name]
}

// Set Warning
func (f *Form) SetWarning(name, warning string) {
    if f.Data == nil {
        f.Data = &FormData{}
    }
    if f.Data.Warning == nil {
        f.Data.Warning = map[string]string{}
    }
    f.Data.Warning[name] = warning
}

// Returns Warning Format
func (f *Form) WarningFormat() string {
    return `<p>%v</p>`
}

// Return Group Format
func (f *Form) Group() string {
    return `%v`
}

// Return Group Format Success
func (f *Form) GroupSuccess() string {
    return `%v`
}

// Return Group Error Format
func (f *Form) GroupError() string {
    return `%v`
}

// Return Group Warning Format
func (f *Form) GroupWarning() string {
    return `%v`
}

// Wrap around Form Input
func (f *Form) Wrap() string {
    return `%v`
}

// Been Checked
func (f *Form) BeenChecked() bool {
    if f.Data == nil {
        return false
    }
    return f.Data.Checked
}

// Mark as Checked
func (f *Form) Check() {
    if f.Data == nil {
        f.Data = &FormData{}
    }
    f.Data.Checked = true
}

// Form Interface
type FormInterface interface {
    Err(string) error
    SetErr(string, error)
    HasErr() bool
    ErrFormat() string
    GetWarning(string) string
    SetWarning(string, string)
    WarningFormat() string
    Group() string
    GroupSuccess() string
    GroupError() string
    GroupWarning() string
    Wrap() string
    BeenChecked() bool
    Check()
}

// A String that implement the error interface
type FormError string

func (f FormError) Error() string {
    return string(f)
}

func init() {
    gob.Register(&Form{})
    gob.Register(FormError(""))
    gob.Register(&FormData{})
}

type form struct {
    m                         reflect.Value
    t                         reflect.Type
    v                         reflect.Value
    field                     reflect.StructField
    value                     reflect.Value
    name, preferedName, ftype string
}

func (f form) get(suffix string) interface{} {
    m := f.m.MethodByName(f.name + suffix)
    if !m.IsValid() {
        return nil
    }
    in := make([]reflect.Value, 0)
    values := m.Call(in)
    if len(values) == 0 {
        return nil
    }
    return values[0].Interface()
}

func (f form) getStr(suffix string) (string, bool) {
    str, ok := f.get(suffix).(string)
    return str, ok
}

func (f form) getStrs(suffix string) ([]string, bool) {
    strs, ok := f.get(suffix).([]string)
    return strs, ok
}

func (f form) getStrMap(suffix string) (map[string]string, bool) {
    mstr, ok := f.get(suffix).(map[string]string)
    return mstr, ok
}

func (f form) getInt(suffix string) (int64, bool) {
    num, ok := f.get(suffix).(int64)
    return num, ok
}

func (f form) getFloat(suffix string) (float64, bool) {
    num, ok := f.get(suffix).(float64)
    return num, ok
}

func (f form) getBool(suffix string) (bool, bool) {
    b, ok := f.get(suffix).(bool)
    return b, ok
}

func (f form) getRegExp(suffix string) (*regexp.Regexp, bool) {
    re, ok := f.get(suffix).(*regexp.Regexp)
    return re, ok
}

func (f form) getTime(suffix string) (time.Time, bool) {
    _time, ok := f.get(suffix).(time.Time)
    return _time, ok
}