go简单模拟Redis数据库对应{key, value}的存取功能

源代码：

package main

import (
    "fmt"
)

type M_Rcd map[string]string

type T_Tbl struct {
    tblname string
    record  M_Rcd
}

type T_Kvdb struct {
    dbname string
    tbl    []T_Tbl
}

func (this *T_Kvdb) createDB(db T_Kvdb) {
    this.dbname = db.dbname
    this.tbl = make([]T_Tbl, 5)
    fmt.Printf("\ncreate db \"%s\" success.\n", this.dbname)
}

func (this *T_Kvdb) newTbl(tblname string) T_Tbl {
    var tbl T_Tbl
    var length int
    tbl.tblname = tblname
    tbl.record = make(M_Rcd)

    this.tbl = append(this.tbl, tbl)
    length = len(this.tbl)
    fmt.Printf("add new table \"%s\" to db \"%s\" success.\n", tblname, this.dbname)
    return this.tbl[length-1]
}

/*
 * 思路：循环检索数据库是否有该表，如果有该表，则进一步检索是否有该Key，如有则输出
 */
func (this *T_Kvdb) read(key string, tbl T_Tbl) {
    for i, _ := range this.tbl {
        if this.tbl[i].tblname == tbl.tblname {
            for k, v := range this.tbl[i].record {
                if key == k {
                    fmt.Printf("find result : {%s}\n", v)
                    return
                }
            }
        }
    }
    fmt.Printf("have no table: \"%s\"\n", tbl.tblname)
}

/*
 * 对表进行写数据
 * 参数：
 *        key:   键值
 *        value: 键值对应的数据
 *        tbl:   需要写如数据的表
 */
func (this *T_Kvdb) write(key string, value string, tbl T_Tbl) {
    fmt.Printf("add {%s, %s} to table \"%s\"", key, value, tbl.tblname)
    for i, _ := range this.tbl {
        if this.tbl[i].tblname == tbl.tblname {
            this.tbl[i].record[key] = value /* 对Table写入数据 */
            fmt.Println(" success.")
            return
        }
    }

    fmt.Println("have no table: ", tbl.tblname)
}

/*
 * 删除表中key对应的{key, value}
 */
func (this *T_Kvdb) delete(key string, tbl T_Tbl) {

    for i, _ := range this.tbl {
        if this.tbl[i].tblname == tbl.tblname {
            for k, _ := range this.tbl[i].record {
                if key == k {
                    delete(this.tbl[i].record, key) // 删除key对应的数据{key, value}
                    fmt.Printf("delete key success.\n")
                    this.show()
                    return
                }
            }
        }
    }

    fmt.Printf("have no table: %s\n", tbl.tblname)
}

/*
 * 显示DB里所有Table的数据：{key, value}
 */
func (this *T_Kvdb) show() {
    fmt.Print("show [")
    for i, _ := range this.tbl {
        for key, value := range this.tbl[i].record {
            fmt.Print("{", key, ", ", value, "}")
        }
    }

    fmt.Print("]\n")
}

/*
 * 销毁表的思路：
 *      如有表数组[5]={表0，表1，表2，表3，表4}，现在需要删除{表2}，则可以利用append函数重新组合表数组
 *      来达到删除{表2}. 重组表数组的语句为：append(表头到表2（此处是开区间），（此处是闭区间）表3到表尾)
 */
func (this *T_Kvdb) destroy(tbl T_Tbl) {
    for i, _ := range this.tbl {
        if this.tbl[i].tblname == tbl.tblname {
            this.tbl = append(this.tbl[:i], this.tbl[i+1:]...)
            fmt.Printf("destroy table success.\n")
            return
        }
    }
    fmt.Printf("have no table: \n", tbl.tblname)
}

func main() {
    var db T_Kvdb
    var tbl T_Tbl

    db.dbname = "student_management_system"
    db.createDB(db)
    tbl = db.newTbl("student")
    db.write("hezhixiong", "shanghai", tbl)
    db.write("zhangsan", "beijing", tbl)
    db.show()
    db.read("hezhixiong", tbl)
    db.delete("hezhixiong", tbl)
    fmt.Printf("db size = %d\n", len(db.tbl))
    db.destroy(tbl)
    fmt.Printf("db size = %d\n", len(db.tbl))
}

程序输出：

create db "student_management_system" success.
add new table "student" to db "student_management_system" success.
add {hezhixiong, shanghai} to table "student" success.
show [{hezhixiong, shanghai}]
find result : {shanghai}
delete key success.
show []
db size = 6
destroy table success.
db size = 5