代码仓库 https://gitee.com/zjf1998/FMDBSwift
什么是FMDB:
由于iOS中使用C语言函数对原生SQLite数据库进行增删改查操作,复杂麻烦,所以就出现了一系列的SQLite API封装库,如FMDB。
FMDB是针对libsqlite3框架进行封装的三方,它以OC的方式封装了SQLite的C语言的API,使用步骤与SQLite相似
FMDB优点:
1.使用面向对象,避免了复杂的C语言
2.对比苹果自带的Core Data框架,更加轻量级和灵活
3.提供了多线程安全处理数据库方法,保证安全和数据准确性
FMDB 在Git上的下载链接地址:https://github.com/ccgus/fmdb
主要对象:
1.FMDatabase: 数据库对象,一个对象代表一个数据库,通过sqlite可进行增删改查
2.FMDatabaseQueue:多线程安全操作数据库 保证数据安全
3.FMResultSet: 返回操作数据库后的结果集
开始吧:
1.导入fmdb文件夹:
2.桥接文件:
#import "FMDB.h"
3.创建单例类 DatabaseHelper
//
// DatabaseHelper.swift
// FMDBSwift
//
// Created by sjl on 2019/4/26.
// Copyright © 2019年 zjut. All rights reserved.
//
import UIKit
class DatabaseHelper: NSObject {
//单例类
private static let manger: DatabaseHelper = DatabaseHelper()
class func shareManger() -> DatabaseHelper {
return manger
}
var dbQueue:FMDatabaseQueue? //多线程安全操作数据库 保证数据安全
//初始化
func initDatabase() {
let db = self.getDBQueue()
db.inDatabase { (db) in
//创建
self.createTable(db: db)
}
}
//初始化 FMDatabaseQueue(多线程安全)
func getDBQueue() -> FMDatabaseQueue {
if dbQueue == nil {
let dbPath = self.getDataBasePath()
dbQueue = FMDatabaseQueue(path: dbPath)
}
return dbQueue!
}
//获取db存放路径
func getDataBasePath() -> String{
let docuPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]
let dbPath = docuPath.appending("/aliwatch.db")
print("\(dbPath)")
return dbPath
}
//创建表
func createTable(db: FMDatabase){
let sql = "CREATE TABLE IF NOT EXISTS t_list_watch (" +
"'_id' INTEGER PRIMARY KEY AUTOINCREMENT," +
"'name' TEXT NOT NULL," +
"'age' INTEGER DEFAULT 0)"
let result = db.executeUpdate(sql, withArgumentsIn: [])
if result {
print("create t_list_watch sucessfully!")
}
}
//插入数据
func insertWatchInfo(name: String,age: Int) {
// DatabaseHelper.shareInstance 是个单例类
let db: FMDatabaseQueue = DatabaseHelper.manger.getDBQueue()
db.inTransaction { (db, rollback) in
let sql = "INSERT INTO t_list_watch (name,age) VALUES (?,?)"
let result = db.executeUpdate(sql, withArgumentsIn: [name, age])
if result {
print("DB insert \(name) success")
} else {
print("DB insert \(name) fail")
}
}
}
//查询数据
func getList() {
let db = DatabaseHelper.manger.getDBQueue()
db.inTransaction { (db, rollback) in
let sql = "SELECT * FROM t_list_watch"
let resultSet = db.executeQuery(sql, withArgumentsIn: [])
guard resultSet != nil else {return}
while(resultSet!.next()) {
print(resultSet?.string(forColumn: "name") as Any)
print(resultSet?.string(forColumn: "age") as Any)
}
}
}
//删除
func delectByID(id:String) {
let db = DatabaseHelper.manger.getDBQueue()
db.inTransaction { (db, rollback) in
let sql = "delete from 't_list_watch' where _id = ?"
let result = db.executeUpdate(sql, withArgumentsIn: [id])
if result {
print("DB delect \(id) success")
} else {
print("DB delect \(id) fail")
}
}
}
//更新
func updateByID(id:String,name: String) {
let db = DatabaseHelper.manger.getDBQueue()
db.inTransaction { (db, rollback) in
let sql = "update 't_list_watch' set name = ? where _id = ?"
let result = db.executeUpdate(sql, withArgumentsIn: [name,id])
if result {
print("DB update \(id) success")
} else {
print("DB update \(id) fail")
}
}
}
}
初始化数据库:
DatabaseHelper.shareManger().initDatabase()
插入数据 :
DatabaseHelper.shareManger().insertWatchInfo(name: "zhangsan", age: 18)
DatabaseHelper.shareManger().insertWatchInfo(name: "lisi", age: 20)
查找数据
DatabaseHelper.shareManger().getList()
//修改数据
DatabaseHelper.shareManger().updateByID(id: "1", name: "王五")
//删除数据
DatabaseHelper.shareManger().delectByID(id: "1")