Update README.md

Author: xushiwei

README.md

@@ -8,9 +8,9 @@ yap - Yet Another Go/Go+ HTTP Web Framework
 [![GoDoc](https://pkg.go.dev/badge/github.com/goplus/yap.svg)](https://pkg.go.dev/github.com/goplus/yap)
 [![Language](https://img.shields.io/badge/language-Go+-blue.svg)](https://github.com/goplus/gop)
 
-This repo contains three [Go+ classfiles](https://github.com/goplus/gop/blob/main/doc/classfile.md): `yap` (a HTTP Web Framework), `yaptest` (a HTTP Test Framework) and `ydb` (a Go+ Database Framework).
+This repo contains three [Go+ classfiles](https://github.com/goplus/gop/blob/main/doc/classfile.md). They are [yap](#yap-http-web-framework) (a HTTP Web Framework), [yaptest](ytest) (a HTTP Test Framework) and [ydb](ydb) (a Go+ Database Framework).
 
-The classfile `yap` has the file suffix `.yap`. The classfile `yaptest` has the file suffix `_ytest.gox`. And the classfile `ydb` has the file suffix `_ydb.gox`.
+The classfile [yap](#yap-http-web-framework) has the file suffix `.yap`. The classfile [yaptest](ytest) has the file suffix `_ytest.gox`. And the classfile [ydb](ydb) has the file suffix `_ydb.gox`.
 
 Before using `yap`, `yaptest` or `ydb`, you need to add `github.com/goplus/yap` to `go.mod`: