主要是用sqlite3来存储聊天记录

先导入sqlite3.dylib, 点 Add Other, 同时按住 shift + command + G , 在弹出的 Go to the folder 中输入 /usr/lib/libsqlite3.dylib, 就 OK 了. 还需要#import<sqlite3.h>

1.new file 一个 Text 类用来存储, .m 无需操作



1 #import <Foundation/Foundation.h>
2 
3 @interface Text : NSObject
4 //聊天内容
5 @property(nonatomic,copy)NSString *userText;
6 //聊天内容发送的时间
7 @property(nonatomic,copy)NSString *currentTime;
8 @end



2.另封装一个 TextModel 类用来操作数据



1 #import <Foundation/Foundation.h>
 2 #import <sqlite3.h>
 3 @class Text;
 4 @interface TextModel : NSObject
 5 //建表
 6 -(BOOL)createList:(sqlite3 *)db;
 7 //插入
 8 -(BOOL)insertList:(Text *)insertList;
 9 //获取数据
10 -(NSMutableArray *)getList;
11 @end



.m



//
//  TextModel.m
//  保存聊天记录
//
//  Copyright © 2016年 736376103@qq.com. All rights reserved.
//

#import "TextModel.h"
#import "Text.h"
@implementation TextModel
//定义一个变量
static sqlite3 *_database;

-(NSString *)filename{
    NSString *path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];
    //这里打印,是方便用MesaSQLite打开sqlite3文件,可以增删改查,非常方便,主要是免费(有时间限制)~~~
    NSLog(@"%@",path);
    return [path stringByAppendingPathComponent:@"LIKE.sqlite"];
}

-(BOOL)openDB{
    //获取路径
    NSString *path = [self filename];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    //判断数据库是否存在
    BOOL find = [fileManager fileExistsAtPath:path];
    //如果为真,就打开数据库,不存在,自动创建
    if (find) {
        NSLog(@"database存在");
        
        if (sqlite3_open([path UTF8String], &_database)!=SQLITE_OK) {
            //failed关闭,据说这个习惯好,不明觉厉
            sqlite3_close(_database);
            NSLog(@"打开database失败");
            return NO;
        }
        //建表
        [self createList:_database];
        return YES;
    }
    //同上
    if (sqlite3_open(path.UTF8String, &_database) == SQLITE_OK) {
        [self createList:_database];
        return YES;
    }else{
        sqlite3_close(_database);
        NSLog(@"打开database失败");
        return NO;
    }
        return NO;
    
}
#pragma mark -- 建表
-(BOOL)createList:(sqlite3 *)db{
    //我这里缺少一个主键,自己加上即可--ID INTEGER PRIMARY KEY AUTOINCREMENT
    NSString *sql = [NSString stringWithFormat:@"CREATE TABLE IF NOT EXISTS DRINK(userText TEXT,currentTime TEXT)"];
    sqlite3_stmt *stmt;
    //sqlite3_prepare_v2 接口把一条SQL语句解析到statement结构里去. 使用该接口访问数据库是当前比较好的的一种方法
    NSInteger sqlReturn = sqlite3_prepare_v2(_database, sql.UTF8String, -1, &stmt, NULL);
    //-1是sql语句的长度,<0会自动计算
    if (sqlReturn != SQLITE_OK) {
        NSLog(@"创建表失败");
        return NO;
    }
    int success = sqlite3_step(stmt);
    //释放stmt
    sqlite3_finalize(stmt);
    if (success != SQLITE_DONE) {
        NSLog(@"创建表失败");
        return NO;
    }
    NSLog(@"创建表成功");
    return YES;
}
#pragma mark -- 插入
-(BOOL)insertList:(Text *)insertList{

    if ([self openDB])
    {
        sqlite3_stmt *stmt;
        // ? 表示待会儿插入
        NSString *sql = [NSString stringWithFormat:@"INSERT INTO DRINK(userText,currentTime)VALUES(?,?)"];
        //int success = sqlite3_exec(_database, sql.UTF8String, NULL, NULL, &error);
        int success = sqlite3_prepare_v2(_database, sql.UTF8String, -1, &stmt, NULL);
        if (success != SQLITE_OK) {
            NSLog(@"insert failed");
            sqlite3_close(_database);
            return NO;
        }
        sqlite3_bind_text(stmt, 1, [insertList.userText UTF8String], -1, SQLITE_TRANSIENT);
        sqlite3_bind_text(stmt, 2, [insertList.currentTime UTF8String], -1, SQLITE_TRANSIENT);
        //执行插入语句
        success = sqlite3_step(stmt);
        //释放stmt
        sqlite3_finalize(stmt);
        NSLog(@"%@",insertList.userText);
        NSLog(@"%@",insertList.currentTime);
        //如果failed
        if (success == SQLITE_ERROR) {
            NSLog(@"failed insert into database");
            sqlite3_close(_database);
            return NO;
        }
        sqlite3_close(_database);
        return YES;
    }
    return NO;
}
#pragma mark -- 获取
-(NSMutableArray *)getList{
    NSMutableArray *array = nil;
    //判断是否打开,这里可以用 dispatch_once 只执行一次
    if ([self openDB]) {
        sqlite3_stmt *stmt;
        NSString *sql = [NSString stringWithFormat:@"SELECT userText,currentTime FROM DRINK"];
        if (sqlite3_prepare_v2(_database, sql.UTF8String, -1, &stmt, NULL) != SQLITE_OK) {
            NSLog(@"failed to get list");
        }else{
            array = [NSMutableArray array];
            //遍历记录,这里是从0开始,别写错了
            while (sqlite3_step(stmt) == SQLITE_ROW) {
                Text *p = [[Text alloc]init];
                char *strText = (char *)sqlite3_column_text(stmt, 0);
                //做个判断,如果记录为nil,不执行,这里自己要想一下,为什么要判断
                if (strText != NULL) {
                    p.userText = [NSString stringWithUTF8String:strText];
                }
                char *strTime = (char *)sqlite3_column_text(stmt, 1);
                //时间为Null,不执行
                if (strTime != NULL) {
                    p.currentTime = [NSString stringWithUTF8String:strTime];
                }
                //加进可变数组
                [array addObject:p];
            }
        }
        //释放stmt
        sqlite3_finalize(stmt);
        sqlite3_close(_database);
    }
    return array;
}
@end



3.ViewController.h, 在 storyboard 拖一个 tableView 和一个 textField



#import <UIKit/UIKit.h>
@interface ViewController : UIViewController

@property (weak, nonatomic) IBOutlet UITableView *tableview;

@property (weak, nonatomic) IBOutlet UITextField *textField;

@end



.m



//
//  ViewController.m
//  保存聊天记录
//
//  Created by 736376103@qq.com on 16/4/4.
//  Copyright © 2016年 736376103@qq.com. All rights reserved.
//

#import "ViewController.h"
#import "TableViewCell.h"
#import "Text.h"
#import "TextModel.h"
//实现 UITablevView 和 UITextField 的代理
@interface ViewController ()<UITableViewDataSource,UITableViewDelegate,UITextFieldDelegate>
//数据源
@property(nonatomic,strong)NSMutableArray *dataSource;
//处理数据的类
@property(nonatomic,strong)TextModel *textModel;

@end

@implementation ViewController
//加载数据
-(void)reloadDataSource{
    if (_textModel == nil) {
        _textModel = [[TextModel alloc]init];
    }
    //获取数据
    _dataSource = [_textModel getList];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    //设置代理
    _textField.delegate = self;
    //调用加载数据方法
    [self reloadDataSource];

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
}

-(void)sendMessageContent:(NSString *)text {
    //获取时间
    NSDate *date = [NSDate date];
    NSDateFormatter *dateForMatter = [[NSDateFormatter alloc]init];
    //hh:mm 是 09:54 这样的格式,可以自由发挥
    dateForMatter.dateFormat = @"hh:mm";
    NSString *timeString = [dateForMatter stringFromDate:date];
    
    Text *t = [[Text alloc]init];
    //把时间存到 Text 的属性
    t.currentTime = timeString;
    //输入的内容
    t.userText = text;
    //插入到数据库
    [_textModel insertList:t];
}
#pragma mark -- UITextField代理
-(BOOL)textFieldShouldReturn:(UITextField *)textField{
    //自定义方法,把输入的内容存到 Text
    [self sendMessageContent:textField.text];
    //取消第一响应
    [textField resignFirstResponder];
    //清空键盘
    textField.text = @"";
    //插入之后,加载一次数据,相当于往数据源里加数据
    [self reloadDataSource];
    //刷新界面,显示刚插入的数据
    [_tableview reloadData];
    return YES;
}

#pragma mark - TableView 数据源
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    return _dataSource.count;
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    
    Text *p = _dataSource[indexPath.row];
    //自定义 cell
    TableViewCell *cell = [TableViewCell tableView:tableView];
    //cell 不可点击
    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    cell.timeLabel.text = p.currentTime;
    cell.OtherLabel.text = p.userText;
    return cell;
}
#pragma mark - 代理方法
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
    return 80;
}
@end



4.自定义 cell



#import <UIKit/UIKit.h>

@interface TableViewCell : UITableViewCell
//聊天内容
@property (strong, nonatomic)UILabel *OtherLabel;
//时间
@property (strong, nonatomic)UILabel *timeLabel;
//头像,这个自己随便找个图
@property(strong,nonatomic)UIImageView *meImageView;

+(instancetype)tableView:(UITableView *)tableView;

@end



.m



//
//  TableViewCell.m
//  保存聊天记录
//
//  Created by 736376103@qq.com on 16/4/4.
//  Copyright © 2016年 736376103@qq.com. All rights reserved.
//

#import "TableViewCell.h"

@implementation TableViewCell
//初始化的时候,创建控件
-(id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier{
    if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {
        
        CGFloat width = [UIScreen mainScreen].bounds.size.width;
        
        _OtherLabel = [[UILabel alloc]initWithFrame:CGRectMake(0, 40, width-40, 30)];
        _OtherLabel.font = [UIFont systemFontOfSize:16];
        _OtherLabel.numberOfLines = 0;
        _OtherLabel.lineBreakMode = NSLineBreakByTruncatingTail;
        _OtherLabel.textAlignment = NSTextAlignmentRight;
        [self.contentView addSubview:_OtherLabel];
        
        _timeLabel = [[UILabel alloc]initWithFrame:CGRectMake(width/2-20, 0, 40, 20)];
        _timeLabel.font = [UIFont systemFontOfSize:12];
        [self.contentView addSubview:_timeLabel];
        
        _meImageView = [[UIImageView alloc]initWithFrame:CGRectMake(width-40, 10, 30, 30)];
        _meImageView.image = [UIImage imageNamed:@"003"];
        [self.contentView addSubview:_meImageView];
    }
    return self;
}


+(instancetype)tableView:(UITableView *)tableView{
    TableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"ChatTableViewCell"];
    //cell 复用
    if (cell == nil) {
        cell = [[TableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"ChatTableViewCell"];
    }
    return cell;
}


@end