Issues with the go language about in-package functions for external calls

1. When defining externally accessed structures and methods within the Go Language pack, be careful to capitalize the first letter of the struct name and struct field

For example: Define the structure required for a database:

Type database struct {

　　　　　　db *sql. Db

　　　　　　eRR Error

}

The name of the struct and the field in the struct are not capitalized, and the error type (not defined or not found) is the correct usage:

Type Database struct{

　　　　　　Db *sql. Db

　　　　　　ERR Error

}

2. When defining a method for a struct, you need to capitalize the first letter of the method name

　 In a struct's method, the first letter of the method name also needs to be capitalized, and no corresponding method can be found in Golang

Issues with the go language about in-package functions for external calls