我正在尝试为基于 GIN 框架的基于 Go 的 Web 应用程序添加验证。在网页上,我正在选择一个文件并提交,服务器正在处理它。在服务器端,我尝试添加验证以检查文件是否已提供。如果没有,则重定向回原始页面。
func panic(err error) {
if err != nil {
log.Println(err)
}
}
func displayTable (c *gin.Context) {
file, _ , err := c.Request.FormFile("file")
panic(err)
if file == nil {
log.Println("File is nil.")
log.Println(err)
log.Println("*****")
c.HTML(http.StatusInternalServerError, "index.tmpl", gin.H{
"title": "Select the input file","error" : "Please select the input file.",
})
} else {
defer file.Close()
}
filename := strconv.FormatInt(time.Now().Unix(),10)
out, err := os.Create("./tmp/"+filename+".xml")
panic(err)
defer out.Close()
_, err = io.Copy(out, file)
panic(err)
xmlFile, err := os.Open("./tmp/"+filename+".xml")
panic(err)
defer xmlFile.Close()
// Other Implementation Details
}
即使在提供处理之后,我也会在 go 代码中感到恐慌。请让我知道我在实施中缺少什么。
谢谢。
http: no such file
File is nil.
http: no such file
*****
2015/08/04 13:19:10 Panic recovery -> runtime error: invalid memory address or nil pointer dereference
c:/go/src/runtime/panic.go:387 (0x414d36)
c:/go/src/runtime/panic.go:42 (0x4142a5)
c:/go/src/runtime/os_windows.go:42 (0x414066)
c:/go/src/io/io.go:362 (0x45268f)
D:/code/src/exmp/serverexmaple.go:45 (0x40168f)
displayTable: _, err = io.Copy(out, file)
D:/code/src/github.com/gin-gonic/gin/context.go:95 (0x49f8ea)
(*Context).Next: c.handlers[c.index](c)
D:/code/src/github.com/gin-gonic/gin/logger.go:56 (0x4ac490)
func.007: c.Next()
D:/code/src/github.com/gin-gonic/gin/context.go:95 (0x49f8ea)
(*Context).Next: c.handlers[c.index](c)
D:/code/src/github.com/gin-gonic/gin/recovery.go:43 (0x4acc80)
func.009: c.Next()
D:/code/src/github.com/gin-gonic/gin/context.go:95 (0x49f8ea)
(*Context).Next: c.handlers[c.index](c)
D:/code/src/github.com/gin-gonic/gin/gin.go:292 (0x4a46d5)
(*Engine).handleHTTPRequest: context.Next()
D:/code/src/github.com/gin-gonic/gin/gin.go:273 (0x4a4459)
(*Engine).ServeHTTP: engine.handleHTTPRequest(c)
c:/go/src/net/http/server.go:1703 (0x468415)
c:/go/src/net/http/server.go:1204 (0x466408)
c:/go/src/runtime/asm_386.s:2287 (0x438ea1)