133 lines
3.4 KiB
Markdown
133 lines
3.4 KiB
Markdown
# Copier
|
|
|
|
I am a copier, I copy everything from one to another
|
|
|
|
[](https://github.com/jinzhu/copier/actions)
|
|
|
|
## Features
|
|
|
|
* Copy from field to field with same name
|
|
* Copy from method to field with same name
|
|
* Copy from field to method with same name
|
|
* Copy from slice to slice
|
|
* Copy from struct to slice
|
|
* Copy from map to map
|
|
* Enforce copying a field with a tag
|
|
* Ignore a field with a tag
|
|
* Deep Copy
|
|
|
|
## Usage
|
|
|
|
```go
|
|
package main
|
|
|
|
import (
|
|
"fmt"
|
|
"github.com/jinzhu/copier"
|
|
)
|
|
|
|
type User struct {
|
|
Name string
|
|
Role string
|
|
Age int32
|
|
EmployeCode int64 `copier:"EmployeNum"` // specify field name
|
|
|
|
// Explicitly ignored in the destination struct.
|
|
Salary int
|
|
}
|
|
|
|
func (user *User) DoubleAge() int32 {
|
|
return 2 * user.Age
|
|
}
|
|
|
|
// Tags in the destination Struct provide instructions to copier.Copy to ignore
|
|
// or enforce copying and to panic or return an error if a field was not copied.
|
|
type Employee struct {
|
|
// Tell copier.Copy to panic if this field is not copied.
|
|
Name string `copier:"must"`
|
|
|
|
// Tell copier.Copy to return an error if this field is not copied.
|
|
Age int32 `copier:"must,nopanic"`
|
|
|
|
// Tell copier.Copy to explicitly ignore copying this field.
|
|
Salary int `copier:"-"`
|
|
|
|
DoubleAge int32
|
|
EmployeId int64 `copier:"EmployeNum"` // specify field name
|
|
SuperRole string
|
|
}
|
|
|
|
func (employee *Employee) Role(role string) {
|
|
employee.SuperRole = "Super " + role
|
|
}
|
|
|
|
func main() {
|
|
var (
|
|
user = User{Name: "Jinzhu", Age: 18, Role: "Admin", Salary: 200000}
|
|
users = []User{{Name: "Jinzhu", Age: 18, Role: "Admin", Salary: 100000}, {Name: "jinzhu 2", Age: 30, Role: "Dev", Salary: 60000}}
|
|
employee = Employee{Salary: 150000}
|
|
employees = []Employee{}
|
|
)
|
|
|
|
copier.Copy(&employee, &user)
|
|
|
|
fmt.Printf("%#v \n", employee)
|
|
// Employee{
|
|
// Name: "Jinzhu", // Copy from field
|
|
// Age: 18, // Copy from field
|
|
// Salary:150000, // Copying explicitly ignored
|
|
// DoubleAge: 36, // Copy from method
|
|
// EmployeeId: 0, // Ignored
|
|
// SuperRole: "Super Admin", // Copy to method
|
|
// }
|
|
|
|
// Copy struct to slice
|
|
copier.Copy(&employees, &user)
|
|
|
|
fmt.Printf("%#v \n", employees)
|
|
// []Employee{
|
|
// {Name: "Jinzhu", Age: 18, Salary:0, DoubleAge: 36, EmployeId: 0, SuperRole: "Super Admin"}
|
|
// }
|
|
|
|
// Copy slice to slice
|
|
employees = []Employee{}
|
|
copier.Copy(&employees, &users)
|
|
|
|
fmt.Printf("%#v \n", employees)
|
|
// []Employee{
|
|
// {Name: "Jinzhu", Age: 18, Salary:0, DoubleAge: 36, EmployeId: 0, SuperRole: "Super Admin"},
|
|
// {Name: "jinzhu 2", Age: 30, Salary:0, DoubleAge: 60, EmployeId: 0, SuperRole: "Super Dev"},
|
|
// }
|
|
|
|
// Copy map to map
|
|
map1 := map[int]int{3: 6, 4: 8}
|
|
map2 := map[int32]int8{}
|
|
copier.Copy(&map2, map1)
|
|
|
|
fmt.Printf("%#v \n", map2)
|
|
// map[int32]int8{3:6, 4:8}
|
|
}
|
|
```
|
|
|
|
### Copy with Option
|
|
|
|
```go
|
|
copier.CopyWithOption(&to, &from, copier.Option{IgnoreEmpty: true, DeepCopy: true})
|
|
```
|
|
|
|
## Contributing
|
|
|
|
You can help to make the project better, check out [http://gorm.io/contribute.html](http://gorm.io/contribute.html) for things you can do.
|
|
|
|
# Author
|
|
|
|
**jinzhu**
|
|
|
|
* <http://github.com/jinzhu>
|
|
* <wosmvp@gmail.com>
|
|
* <http://twitter.com/zhangjinzhu>
|
|
|
|
## License
|
|
|
|
Released under the [MIT License](https://github.com/jinzhu/copier/blob/master/License).
|