吕滔博客

Gin获取输入数据还是挺复杂的，这里简单总结一下：

• Get的使用Query、Param系列
• Post的form-data和x-www-form-urlencoded使用PostForm系列
• Get和Post的数据都可以用Bind、ShouldBind系列，不过结构体的tag需要写正确
• 文件上传使用form-data，通过函数FormFile或者MultipartForm

详解：
Param

// Param returns the value of the URL param.
// It is a shortcut for c.Params.ByName(key)
router.GET("/user/:id", func(c *gin.Context) {
    // a GET request to /user/john
    id := c.Param("id") // id == "john"
})
func (c *Context) Param(key string) string

AddParam

// AddParam adds param to context and
// replaces path param key with given value for e2e testing purposes
// Example Route: "/user/:id"
// AddParam("id", 1)
// Result: "/user/1"
func (c *Context) AddParam(key, value string) 

Query

// Query returns the keyed url query value if it exists,
// otherwise it returns an empty string `("")`.
// It is shortcut for `c.Request.URL.Query().Get(key)`
//     GET /path?id=1234&name=Manu&value=
// 	   c.Query("id") == "1234"
// 	   c.Query("name") == "Manu"
// 	   c.Query("value") == ""
// 	   c.Query("wtf") == ""
func (c *Context) Query(key string) (value string)

DefaultQuery

// DefaultQuery returns the keyed url query value if it exists,
// otherwise it returns the specified defaultValue string.
// See: Query() and GetQuery() for further information.
//     GET /?name=Manu&lastname=
//     c.DefaultQuery("name", "unknown") == "Manu"
//     c.DefaultQuery("id", "none") == "none"
//     c.DefaultQuery("lastname", "none") == ""
func (c *Context) DefaultQuery(key, defaultValue string) string 

QueryArray

// QueryArray returns a slice of strings for a given query key.
// The length of the slice depends on the number of params with the given key.
func (c *Context) QueryArray(key string) (values []string)

QueryMap

// QueryMap returns a map for a given query key.
func (c *Context) QueryMap(key string) (dicts map[string]string)

PostForm

// PostForm returns the specified key from a POST urlencoded form or multipart form
// when it exists, otherwise it returns an empty string `("")`.
func (c *Context) PostForm(key string) (value string) 

DefaultPostForm

// DefaultPostForm returns the specified key from a POST urlencoded form or multipart form
// when it exists, otherwise it returns the specified defaultValue string.
// See: PostForm() and GetPostForm() for further information.
func (c *Context) DefaultPostForm(key, defaultValue string) string

PostFormArray

// PostFormArray returns a slice of strings for a given form key.
// The length of the slice depends on the number of params with the given key.
func (c *Context) PostFormArray(key string) (values []string)

PostFormMap

// PostFormMap returns a map for a given form key.
func (c *Context) PostFormMap(key string) (dicts map[string]string)

FormFile

// FormFile returns the first file for the provided form key.
func (c *Context) FormFile(name string) (*multipart.FileHeader, error)

MultipartForm

// MultipartForm is the parsed multipart form, including file uploads.
func (c *Context) MultipartForm() (*multipart.Form, error)

SaveUploadedFile

// SaveUploadedFile uploads the form file to specific dst.
func (c *Context) SaveUploadedFile(file *multipart.FileHeader, dst string) 

Bind

// Bind checks the Method and Content-Type to select a binding engine automatically,
// Depending on the "Content-Type" header different bindings are used, for example:
//     "application/json" --> JSON binding
//     "application/xml"  --> XML binding
// It parses the request's body as JSON if Content-Type == "application/json" using JSON or XML as a JSON input.
// It decodes the json payload into the struct specified as a pointer.
// It writes a 400 error and sets Content-Type header "text/plain" in the response if input is not valid.
func (c *Context) Bind(obj any) error

BindJSON

// BindJSON is a shortcut for c.MustBindWith(obj, binding.JSON).
func (c *Context) BindJSON(obj any) error 

BindXML

// BindXML is a shortcut for c.MustBindWith(obj, binding.BindXML).
func (c *Context) BindXML(obj any) error