Golang Value.Bool方法代碼示例

// convert to float64
func ToFloat(input reflect.Value) (output float64, err error) {
	//defer checkError(err)
	if !input.IsValid() {
		return 0, newTypeErr(methodName(), "input is invalid", input)
	}

	input = Underlying(input)
	k := input.Kind()
	switch {
	case IsBool(k):
		if input.Bool() {
			return 1, nil
		}
		return 0, nil
	case IsInt(k):
		return float64(input.Int()), nil
	case IsUint(k):
		return float64(input.Uint()), nil
	case IsFloat(k):
		return input.Float(), nil
	case IsString(k):
		return strconv.ParseFloat(input.String(), 32)
	default:
	}
	return 0, newTypeErr(methodName(), "input can not convert to float", input)
}

func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) (string, []byte, error) {
	switch val.Kind() {
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
		return strconv.FormatInt(val.Int(), 10), nil, nil
	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
		return strconv.FormatUint(val.Uint(), 10), nil, nil
	case reflect.Float32, reflect.Float64:
		return strconv.FormatFloat(val.Float(), 'g', -1, val.Type().Bits()), nil, nil
	case reflect.String:
		return val.String(), nil, nil
	case reflect.Bool:
		return strconv.FormatBool(val.Bool()), nil, nil
	case reflect.Array:
		if typ.Elem().Kind() != reflect.Uint8 {
			break
		}
		// [...]byte
		var bytes []byte
		if val.CanAddr() {
			bytes = val.Slice(0, val.Len()).Bytes()
		} else {
			bytes = make([]byte, val.Len())
			reflect.Copy(reflect.ValueOf(bytes), val)
		}
		return "", bytes, nil
	case reflect.Slice:
		if typ.Elem().Kind() != reflect.Uint8 {
			break
		}
		// []byte
		return "", val.Bytes(), nil
	}
	return "", nil, &UnsupportedTypeError{typ}
}

// for insert and update
// If already assigned, then just ignore tag
func GetValQuoteStr(val reflect.Value) (string, error) {
	switch val.Kind() {
	case reflect.Bool:
		boolStr := "N"
		if val.Bool() {
			boolStr = "Y"
		}
		return boolStr, nil
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
		return strconv.FormatInt(val.Int(), 10), nil
	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
		return strconv.FormatUint(val.Uint(), 10), nil
	case reflect.Float32, reflect.Float64:
		return strconv.FormatFloat(val.Float(), 'f', -1, 64), nil
	case reflect.String:
		return QuoteStr(val.String()), nil
	case reflect.Slice: //[]byte
		if val.Type().Elem().Name() != "uint8" {
			return "", fmt.Errorf("GetValQuoteStr> slicetype is not []byte: %v", val.Interface())
		}
		return QuoteStr(string(val.Interface().([]byte))), nil
	default:
		return "", fmt.Errorf("GetValQuoteStr> reflect.Value is not a string/int/uint/float/bool/[]byte!\nval: %v", val)
	}
	return "", nil
}

func (c *FlatMapConfig) flatten(result map[string]interface{}, prefix string, v reflect.Value) error {
	var err error

	if v.Kind() == reflect.Interface {
		v = v.Elem()
	}

	// Set as type interface
	// https://golang.org/pkg/reflect/#Kind
	switch v.Kind() {
	case reflect.Bool:
		result[c.keyDelim+prefix] = v.Bool()
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32:
		result[c.keyDelim+prefix] = v.Int()
	case reflect.String:
		result[c.keyDelim+prefix] = v.String()
	case reflect.Map:
		err = c.flattenMap(result, prefix, v)
	case reflect.Slice, reflect.Array:
		err = c.flattenSlice(result, prefix, v)
	default:
		err = fmt.Errorf("Unknown primitive type found for value: '%q'", v)
	}

	return err
}

func (this *databaseImplement) value2Interface(fieldValue reflect.Value) (interface{}, error) {
	fieldType := fieldValue.Type()
	fieldTypeKind := fieldType.Kind()
	switch fieldTypeKind {
	case reflect.Bool:
		return fieldValue.Bool(), nil
	case reflect.String:
		return fieldValue.String(), nil
	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
		return fieldValue.Int(), nil
	case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
		return fieldValue.Uint(), nil
	case reflect.Float32, reflect.Float64:
		return fieldValue.Float(), nil
	case reflect.Struct:
		if fieldType == reflect.TypeOf(time.Time{}) {
			t := fieldValue.Interface().(time.Time)
			tf := t.Format("2006-01-02 15:04:05")
			return tf, nil
		} else {
			return nil, fmt.Errorf("Unsupported type %v", fieldType)
		}
	default:
		return nil, fmt.Errorf("Unsupported type %v", fieldType)
	}
}

func boolEncoder(v reflect.Value) interface{} {
	if v.Bool() {
		return true
	} else {
		return false
	}
}

// valueString returns the string representation of a value.
func valueString(v reflect.Value, opts tagOptions) string {
	for v.Kind() == reflect.Ptr {
		if v.IsNil() {
			return ""
		}
		v = v.Elem()
	}

	if v.Kind() == reflect.Bool && opts.Contains("int") {
		if v.Bool() {
			return "1"
		}
		return "0"
	}

	if v.Type() == timeType {
		t := v.Interface().(time.Time)
		if opts.Contains("unix") {
			return strconv.FormatInt(t.Unix(), 10)
		}
		return t.Format(time.RFC3339)
	}

	return fmt.Sprint(v.Interface())
}

func boolAsStringDecoder(dv, sv reflect.Value) {
	if sv.Bool() {
		dv.SetString("1")
	} else {
		dv.SetString("0")
	}
}

func boolEncoder(e *encodeState, v reflect.Value) {
	if v.Bool() {
		e.WriteString("true")
	} else {
		e.WriteString("false")
	}
}

func boolAsUintDecoder(dv, sv reflect.Value) {
	if sv.Bool() {
		dv.SetUint(1)
	} else {
		dv.SetUint(0)
	}
}

func boolAsFloatDecoder(dv, sv reflect.Value) {
	if sv.Bool() {
		dv.SetFloat(1)
	} else {
		dv.SetFloat(0)
	}
}

func isZero(v reflect.Value) bool {
	switch v.Kind() {
	case reflect.String:
		return len(v.String()) == 0
	case reflect.Ptr, reflect.Interface:
		return v.IsNil()
	case reflect.Slice:
		return v.Len() == 0
	case reflect.Map:
		return v.Len() == 0
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
		return v.Int() == 0
	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
		return v.Uint() == 0
	case reflect.Float32, reflect.Float64:
		return v.Float() == 0
	case reflect.Bool:
		return !v.Bool()
	case reflect.Struct:
		vt := v.Type()
		if vt == typeTime {
			return v.Interface().(time.Time).IsZero()
		}
		for i := 0; i < v.NumField(); i++ {
			if vt.Field(i).PkgPath != "" && !vt.Field(i).Anonymous {
				continue // Private field
			}
			if !isZero(v.Field(i)) {
				return false
			}
		}
		return true
	}
	return false
}

// formatAtom formats a value without inspecting its internal structure.
// It is a copy of the the function in gopl.io/ch11/format.
func formatAtom(v reflect.Value) string {
	switch v.Kind() {
	case reflect.Invalid:
		return "invalid"
	case reflect.Int, reflect.Int8, reflect.Int16,
		reflect.Int32, reflect.Int64:
		return strconv.FormatInt(v.Int(), 10)
	case reflect.Uint, reflect.Uint8, reflect.Uint16,
		reflect.Uint32, reflect.Uint64, reflect.Uintptr:
		return strconv.FormatUint(v.Uint(), 10)
	// ...floating-point and complex cases omitted for brevity...
	case reflect.Bool:
		if v.Bool() {
			return "true"
		}
		return "false"
	case reflect.String:
		return strconv.Quote(v.String())
	case reflect.Chan, reflect.Func, reflect.Ptr,
		reflect.Slice, reflect.Map:
		return v.Type().String() + " 0x" +
			strconv.FormatUint(uint64(v.Pointer()), 16)
	default: // reflect.Array, reflect.Struct, reflect.Interface
		return v.Type().String() + " value"
	}
}

func (p *printer) marshalSimple(typ reflect.Type, val reflect.Value) error {
	// Normally we don't see structs, but this can happen for an attribute.
	if val.Type() == timeType {
		p.WriteString(val.Interface().(time.Time).Format(time.RFC3339Nano))
		return nil
	}
	switch val.Kind() {
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
		p.WriteString(strconv.FormatInt(val.Int(), 10))
	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
		p.WriteString(strconv.FormatUint(val.Uint(), 10))
	case reflect.Float32, reflect.Float64:
		p.WriteString(strconv.FormatFloat(val.Float(), 'g', -1, 64))
	case reflect.String:
		// TODO: Add EscapeString.
		Escape(p, []byte(val.String()))
	case reflect.Bool:
		p.WriteString(strconv.FormatBool(val.Bool()))
	case reflect.Array:
		// will be [...]byte
		bytes := make([]byte, val.Len())
		for i := range bytes {
			bytes[i] = val.Index(i).Interface().(byte)
		}
		Escape(p, bytes)
	case reflect.Slice:
		// will be []byte
		Escape(p, val.Bytes())
	default:
		return &UnsupportedTypeError{typ}
	}
	return p.cachedWriteError()
}

func encodeValue(buf []byte, prefix, name string, fv reflect.Value, inArray, arrayTable bool) ([]byte, error) {
	switch t := fv.Interface().(type) {
	case Marshaler:
		b, err := t.MarshalTOML()
		if err != nil {
			return nil, err
		}
		return appendNewline(append(appendKey(buf, name, inArray, arrayTable), b...), inArray, arrayTable), nil
	case time.Time:
		return appendNewline(encodeTime(appendKey(buf, name, inArray, arrayTable), t), inArray, arrayTable), nil
	}
	switch fv.Kind() {
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
		return appendNewline(encodeInt(appendKey(buf, name, inArray, arrayTable), fv.Int()), inArray, arrayTable), nil
	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
		return appendNewline(encodeUint(appendKey(buf, name, inArray, arrayTable), fv.Uint()), inArray, arrayTable), nil
	case reflect.Float32, reflect.Float64:
		return appendNewline(encodeFloat(appendKey(buf, name, inArray, arrayTable), fv.Float()), inArray, arrayTable), nil
	case reflect.Bool:
		return appendNewline(encodeBool(appendKey(buf, name, inArray, arrayTable), fv.Bool()), inArray, arrayTable), nil
	case reflect.String:
		return appendNewline(encodeString(appendKey(buf, name, inArray, arrayTable), fv.String()), inArray, arrayTable), nil
	case reflect.Slice, reflect.Array:
		ft := fv.Type().Elem()
		for ft.Kind() == reflect.Ptr {
			ft = ft.Elem()
		}
		if ft.Kind() == reflect.Struct {
			name := tableName(prefix, name)
			var err error
			for i := 0; i < fv.Len(); i++ {
				if buf, err = marshal(append(append(append(buf, '[', '['), name...), ']', ']', '\n'), name, fv.Index(i), false, true); err != nil {
					return nil, err
				}
			}
			return buf, nil
		}
		buf = append(appendKey(buf, name, inArray, arrayTable), '[')
		var err error
		for i := 0; i < fv.Len(); i++ {
			if i != 0 {
				buf = append(buf, ',')
			}
			if buf, err = encodeValue(buf, prefix, name, fv.Index(i), true, false); err != nil {
				return nil, err
			}
		}
		return appendNewline(append(buf, ']'), inArray, arrayTable), nil
	case reflect.Struct:
		name := tableName(prefix, name)
		return marshal(append(append(append(buf, '['), name...), ']', '\n'), name, fv, inArray, arrayTable)
	case reflect.Interface:
		var err error
		if buf, err = encodeInterface(appendKey(buf, name, inArray, arrayTable), fv.Interface()); err != nil {
			return nil, err
		}
		return appendNewline(buf, inArray, arrayTable), nil
	}
	return nil, fmt.Errorf("toml: marshal: unsupported type %v", fv.Kind())
}