## 文件上传
### 上传单个文件
#### 服务端
`server.go`
```go
package main
import (
"fmt"
"io"
"os"
"net/http"
"github.com/labstack/echo"
"github.com/labstack/echo/middleware"
)
func upload(c echo.Context) error {
// Read form fields
name := c.FormValue("name")
email := c.FormValue("email")
//-----------
// Read file
//-----------
// Source
file, err := c.FormFile("file")
if err != nil {
return err
}
src, err := file.Open()
if err != nil {
return err
}
defer src.Close()
// Destination
dst, err := os.Create(file.Filename)
if err != nil {
return err
}
defer dst.Close()
// Copy
if _, err = io.Copy(dst, src); err != nil {
return err
}
return c.HTML(http.StatusOK, fmt.Sprintf("<p>File %s uploaded successfully with fields name=%s and email=%s.</p>", file.Filename, name, email))
}
func main() {
e := echo.New()
e.Use(middleware.Logger())
e.Use(middleware.Recover())
e.Static("/", "public")
e.POST("/upload", upload)
e.Logger.Fatal(e.Start(":1323"))
}
```
#### 客户端
`index.html`
```html
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Single file upload</title>
</head>
<body>
<h1>Upload single file with fields</h1>
<form action="/upload" method="post" enctype="multipart/form-data">
Name: <input type="text" name="name"><br>
Email: <input type="email" name="email"><br>
Files: <input type="file" name="file"><br><br>
<input type="submit" value="Submit">
</form>
</body>
</html>
```
### 上传多个文件
#### 服务端
`server.go`
```go
package main
import (
"fmt"
"io"
"os"
"net/http"
"github.com/labstack/echo"
"github.com/labstack/echo/middleware"
)
func upload(c echo.Context) error {
// Read form fields
name := c.FormValue("name")
email := c.FormValue("email")
//------------
// Read files
//------------
// Multipart form
form, err := c.MultipartForm()
if err != nil {
return err
}
files := form.File["files"]
for _, file := range files {
// Source
src, err := file.Open()
if err != nil {
return err
}
defer src.Close()
// Destination
dst, err := os.Create(file.Filename)
if err != nil {
return err
}
defer dst.Close()
// Copy
if _, err = io.Copy(dst, src); err != nil {
return err
}
}
return c.HTML(http.StatusOK, fmt.Sprintf("<p>Uploaded successfully %d files with fields name=%s and email=%s.</p>", len(files), name, email))
}
func main() {
e := echo.New()
e.Use(middleware.Logger())
e.Use(middleware.Recover())
e.Static("/", "public")
e.POST("/upload", upload)
e.Logger.Fatal(e.Start(":1323"))
}
```
#### 客户端
`index.html`
```html
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Multiple file upload</title>
</head>
<body>
<h1>Upload multiple files with fields</h1>
<form action="/upload" method="post" enctype="multipart/form-data">
Name: <input type="text" name="name"><br>
Email: <input type="email" name="email"><br>
Files: <input type="file" name="files" multiple><br><br>
<input type="submit" value="Submit">
</form>
</body>
</html>
```
