binding: add support of multipart multi files (#1878) (#1949)

* binding: add support of multipart multi files (#1878)

* update readme: add multipart file binding

binding/form.go

@@ -5,9 +5,7 @@
 package binding
 
 import (
-	"mime/multipart"
 	"net/http"
-	"reflect"
 )
 
 const defaultMemory = 32 * 1024 * 1024
@@ -63,27 +61,3 @@ func (formMultipartBinding) Bind(req *http.Request, obj interface{}) error {
 
 	return validate(obj)
 }
-
-type multipartRequest http.Request
-
-var _ setter = (*multipartRequest)(nil)
-
-var (
-	multipartFileHeaderStructType = reflect.TypeOf(multipart.FileHeader{})
-)
-
-// TrySet tries to set a value by the multipart request with the binding a form file
-func (r *multipartRequest) TrySet(value reflect.Value, field reflect.StructField, key string, opt setOptions) (isSetted bool, err error) {
-	if value.Type() == multipartFileHeaderStructType {
-		_, file, err := (*http.Request)(r).FormFile(key)
-		if err != nil {
-			return false, err
-		}
-		if file != nil {
-			value.Set(reflect.ValueOf(*file))
-			return true, nil
-		}
-	}
-
-	return setByForm(value, field, r.MultipartForm.Value, key, opt)
-}