go简单模拟Redis数据库对应{key, value}的存取功能

源代码：

  1 package main
  2 
  3 import (
  4     "fmt"
  5 )
  6 
  7 type M_Rcd map[string]string
  8 
  9 type T_Tbl struct {
 10     tblname string
 11     record  M_Rcd
 12 }
 13 
 14 type T_Kvdb struct {
 15     dbname string
 16     tbl    []T_Tbl
 17 }
 18 
 19 func (this *T_Kvdb) createDB(db T_Kvdb) {
 20     this.dbname = db.dbname
 21     this.tbl = make([]T_Tbl, 5)
 22     fmt.Printf("\ncreate db \"%s\" success.\n", this.dbname)
 23 }
 24 
 25 func (this *T_Kvdb) newTbl(tblname string) T_Tbl {
 26     var tbl T_Tbl
 27     var length int
 28     tbl.tblname = tblname
 29     tbl.record = make(M_Rcd)
 30 
 31     this.tbl = append(this.tbl, tbl)
 32     length = len(this.tbl)
 33     fmt.Printf("add new table \"%s\" to db \"%s\" success.\n", tblname, this.dbname)
 34     return this.tbl[length-1]
 35 }
 36 
 37 /*
 38  * 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
 39  */
 40 func (this *T_Kvdb) read(key string, tbl T_Tbl) {
 41     for i, _ := range this.tbl {
 42         if this.tbl[i].tblname == tbl.tblname {
 43             for k, v := range this.tbl[i].record {
 44                 if key == k {
 45                     fmt.Printf("find result : {%s}\n", v)
 46                     return
 47                 }
 48             }
 49         }
 50     }
 51     fmt.Printf("have no table: \"%s\"\n", tbl.tblname)
 52 }
 53 
 54 /*
 55  * 对表进行写数据
 56  * 参数：
 57  *        key:   键值
 58  *        value: 键值对应的数据
 59  *        tbl:   需要写如数据的表
 60  */
 61 func (this *T_Kvdb) write(key string, value string, tbl T_Tbl) {
 62     fmt.Printf("add {%s, %s} to table \"%s\"", key, value, tbl.tblname)
 63     for i, _ := range this.tbl {
 64         if this.tbl[i].tblname == tbl.tblname {
 65             this.tbl[i].record[key] = value /* 对Table写入数据 */
 66             fmt.Println(" success.")
 67             return
 68         }
 69     }
 70 
 71     fmt.Println("have no table: ", tbl.tblname)
 72 }
 73 
 74 /*
 75  * 删除表中key对应的{key, value}
 76  */
 77 func (this *T_Kvdb) delete(key string, tbl T_Tbl) {
 78 
 79     for i, _ := range this.tbl {
 80         if this.tbl[i].tblname == tbl.tblname {
 81             for k, _ := range this.tbl[i].record {
 82                 if key == k {
 83                     delete(this.tbl[i].record, key) // 删除key对应的数据{key, value}
 84                     fmt.Printf("delete key success.\n")
 85                     this.show()
 86                     return
 87                 }
 88             }
 89         }
 90     }
 91 
 92     fmt.Printf("have no table: %s\n", tbl.tblname)
 93 }
 94 
 95 /*
 96  * 显示DB里所有Table的数据：{key, value}
 97  */
 98 func (this *T_Kvdb) show() {
 99     fmt.Print("show [")
100     for i, _ := range this.tbl {
101         for key, value := range this.tbl[i].record {
102             fmt.Print("{", key, ", ", value, "}")
103         }
104     }
105 
106     fmt.Print("]\n")
107 }
108 
109 /*
110  * 销毁表的思路：
111  *      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
112  *      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)
113  */
114 func (this *T_Kvdb) destroy(tbl T_Tbl) {
115     for i, _ := range this.tbl {
116         if this.tbl[i].tblname == tbl.tblname {
117             this.tbl = append(this.tbl[:i], this.tbl[i+1:]...)
118             fmt.Printf("destroy table success.\n")
119             return
120         }
121     }
122     fmt.Printf("have no table: \n", tbl.tblname)
123 }
124 
125 func main() {
126     var db T_Kvdb
127     var tbl T_Tbl
128 
129     db.dbname = "student_management_system"
130     db.createDB(db)
131     tbl = db.newTbl("student")
132     db.write("hezhixiong", "shanghai", tbl)
133     db.write("zhangsan", "beijing", tbl)
134     db.show()
135     db.read("hezhixiong", tbl)
136     db.delete("hezhixiong", tbl)
137     fmt.Printf("db size = %d\n", len(db.tbl))
138     db.destroy(tbl)
139     fmt.Printf("db size = %d\n", len(db.tbl))
140 }
View Code

程序输出：

 1 create db "student_management_system" success.
 2 add new table "student" to db "student_management_system" success.
 3 add {hezhixiong, shanghai} to table "student" success.
 4 show [{hezhixiong, shanghai}]
 5 find result : {shanghai}
 6 delete key success.
 7 show []
 8 db size = 6
 9 destroy table success.
10 db size = 5
View Code

 

posted @ 2015-06-17 15:54  hezhixiong  阅读(572)  评论(0)  编辑  收藏  举报