//For the app I have that did this, the SQLite data was fairly large. Therefore, I used a background thread to export all the data to a CSV (comma separated value) file, which Excel can import, and then opened up a mail composer with the CSV file as an attachment. If your data is small, you might not need to use a background thread:
 
- (IBAction) export: (id) sender
{    
    // in my full code, I start a UIActivityIndicator spinning and show a 
    //  message that the app is "Exporting ..."

    [self performSelectorInBackground: @selector(exportImpl) withObject: nil];
}

 
 
 
//Here is exportImpl
- (void) exportImpl
{
    NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];

    NSArray* documentPaths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSSystemDomainMask, YES);
    NSString* documentsDir = [documentPaths objectAtIndex:0];
    NSString* csvPath = [documentsDir stringByAppendingPathComponent: @"export.csv"];

    // TODO: mutex lock?
    [sqliteDb exportCsv: csvPath];

    [pool release];

    // mail is graphical and must be run on UI thread
    [self performSelectorOnMainThread: @selector(mail:) withObject: csvPath waitUntilDone: NO];
}

- (void) mail: (NSString*) filePath
{
    // here I stop animating the UIActivityIndicator

    // http://howtomakeiphoneapps.com/home/2009/7/14/how-to-make-your-iphone-app-send-email-with-attachments.html
    BOOL success = NO;
    if ([MFMailComposeViewController canSendMail]) {
        // TODO: autorelease pool needed ?
        NSData* database = [NSData dataWithContentsOfFile: filePath];

        if (database != nil) {
            MFMailComposeViewController* picker = [[MFMailComposeViewController alloc] init];
            picker.mailComposeDelegate = self;
            [picker setSubject:[NSString stringWithFormat: @"%@ %@", [[UIDevice currentDevice] model], [filePath lastPathComponent]]];

            NSString* filename = [filePath lastPathComponent];
            [picker addAttachmentData: database mimeType:@"application/octet-stream" fileName: filename];
            NSString* emailBody = @"Attached is the SQLite data from my iOS device.";
            [picker setMessageBody:emailBody isHTML:YES];

            [self presentModalViewController:picker animated:YES];
            success = YES;
            [picker release];
        }
    }

    if (!success) {
        UIAlertView* warning = [[UIAlertView alloc] initWithTitle: @"Error"
                                                          message: @"Unable to send attachment!"
                                                        delegate: self
                                                cancelButtonTitle: @"Ok"
                                                otherButtonTitles: nil];
        [warning show];
        [warning release];
    }
}

 
 
 
//And then, I have a class that encapsulates all my SQLite data. This class is the only one that makes sqlite calls. In this class, I have a method for exporting data into a CSV file in my app's caches directory. The variable sqliteDb in the code above is an instance of this class. Here's the method to export data:
 
 
-(void) exportCsv: (NSString*) filename
{
    // We record this filename, because the app deletes it on exit
    self.tempFile = filename;

    NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
    // Setup the database object
    sqlite3* database;

    // Open the database from the users filessytem
    if (sqlite3_open([self.databasePath UTF8String], &database) == SQLITE_OK)
    {
        [self createTempFile: filename];
        NSOutputStream* output = [[NSOutputStream alloc] initToFileAtPath: filename append: YES];
        [output open];
        if (![output hasSpaceAvailable]) {
            NSLog(@"No space available in %@", filename);
            // TODO: UIAlertView?
        } else {
            NSString* header = @"Source,Time,Latitude,Longitude,Accuracy\n";
            NSInteger result = [output write: [header UTF8String] maxLength: [header length]];
            if (result <= 0) {
                NSLog(@"exportCsv encountered error=%d from header write", result);
            }

            BOOL errorLogged = NO;
            NSString* sqlStatement = @"select timestamp,latitude,longitude,horizontalAccuracy from my_sqlite_table";

            // Setup the SQL Statement and compile it for faster access
            sqlite3_stmt* compiledStatement;
            if (sqlite3_prepare_v2(database, [sqlStatement UTF8String], -1, &compiledStatement, NULL) == SQLITE_OK)
            {
                // Loop through the results and write them to the CSV file
                while (sqlite3_step(compiledStatement) == SQLITE_ROW) {
                    // Read the data from the result row
                    NSInteger secondsSinceReferenceDate = (NSInteger)sqlite3_column_double(compiledStatement, 0);
                    float lat = (float)sqlite3_column_double(compiledStatement, 1);
                    float lon = (float)sqlite3_column_double(compiledStatement, 2);
                    float accuracy = (float)sqlite3_column_double(compiledStatement, 3);

                    if (lat != 0 && lon != 0) {
                        NSDate* timestamp = [[NSDate alloc] initWithTimeIntervalSinceReferenceDate: secondsSinceReferenceDate];
                        NSString* line = [[NSString alloc] initWithFormat: @"%@,%@,%f,%f,%d\n",
                                      table, [dateFormatter stringFromDate: timestamp], lat, lon, (NSInteger)accuracy];
                        result = [output write: [line UTF8String] maxLength: [line length]];
                        if (!errorLogged && (result <= 0)) {
                            NSLog(@"exportCsv write returned %d", result);
                            errorLogged = YES;
                        }
                        [line release];
                        [timestamp release];
                    }
                    // Release the compiled statement from memory
                    sqlite3_finalize(compiledStatement);
                }
            }
        }
        [output close];
        [output release];
    }

    sqlite3_close(database);
    [pool release];
}

-(void) createTempFile: (NSString*) filename {
    NSFileManager* fileSystem = [NSFileManager defaultManager];
    [fileSystem removeItemAtPath: filename error: nil];

    NSMutableDictionary* attributes = [[NSMutableDictionary alloc] init];
    NSNumber* permission = [NSNumber numberWithLong: 0640];
    [attributes setObject: permission forKey: NSFilePosixPermissions];
    if (![fileSystem createFileAtPath: filename contents: nil attributes: attributes]) {
        NSLog(@"Unable to create temp file for exporting CSV.");
        // TODO: UIAlertView?
    }
    [attributes release];
}

 
My code is exporting a database of location information. Obviously, inside exportCsv, you will need to replace my sqlite calls with ones that are appropriate for your database content.
 
Also, the code stores the data in a temporary file. You'll probably want to decide when to clean out those temp files.
 
Obviously, this code was written before ARC was available. Adjust as needed.
 

Export SQLite data to Excel in iOS programmatically(OC)的更多相关文章

  1. Export GridView Data to Excel. 从GridView导出数据到Excel的奇怪问题解析

    GridView导出函数内容如下 string attachment = "attachment; filename=Contacts.xls";            Respo ...

  2. NetSuite SuiteScript 2.0 export data to Excel file(xls)

    In NetSuite SuiteScript, We usually do/implement export data to CSV, that's straight forward: Collec ...

  3. Insert data from excel to database

    USE ESPA Truncate table dbo.Interface_Customer --Delete the table data but retain the structure exec ...

  4. Tutorial: Analyzing sales data from Excel and an OData feed

    With Power BI Desktop, you can connect to all sorts of different data sources, then combine and shap ...

  5. Use JavaScript to Export Your Data as CSV

    原文: http://halistechnology.com/2015/05/28/use-javascript-to-export-your-data-as-csv/ --------------- ...

  6. iOS开发OC基础:Xcode中常见英文总结,OC常见英文错误

    在开发的过程中难免会遇到很多的错误,可是当看到系统给出的英文时,又不知道是什么意思.所以这篇文章总结了Xcode中常见的一些英文单词及词组,可以帮助初学的人快速了解给出的提示.多练习,就肯定能基本掌握 ...

  7. 转载 iOS js oc相互调用(JavaScriptCore) --iOS调用js

    iOS js oc相互调用(JavaScriptCore)   从iOS7开始 苹果公布了JavaScriptCore.framework 它使得JS与OC的交互更加方便了. 下面我们就简单了解一下这 ...

  8. C# Note38: Export data into Excel

    Microsoft.Office.Interop.Excel You have to have Excel installed. Add a reference to your project to ...

  9. ios创建的sqlite数据库文件如何从ios模拟器中导出

    为了验证数据库的结构,有的时候需要使用一些管理工具来直接查看sqlite数据库的内容,在windows下有sqlite3的专用工具下载,而在ios下也可以使用火狐浏览器的插件sqlitemanager ...

随机推荐

  1. 基于神念TGAM的脑波小车(1)

    作者声明:此博客是作者的毕设心得,拿来分享. 拿到模块,在网上查了一圈,发现基本没什么有用的资料,有也是一些废话,经过我几个月的攻克,现在已初步搞定,分享给大家. 废话不多说,直接步入正题. 这是通过 ...

  2. 开源一个最近写的spring与mongodb结合的demo(spring-mongodb-demo)

    由于工作需要,给同事们分享了一下mongodb的使用,其中主要就是做了一个spring-data+mongodb的小例子,本着分享的精神,就上传到了github.com上,有需要的同学请移步githu ...

  3. Linux内核分析— —计算机是如何工作的(20135213林涵锦)

    实验部分 (以下命令为实验楼64位Linux虚拟机环境下适用,32位Linux环境可能会稍有不同) 使用 gcc –S –o main.s main.c -m32 命令编译成汇编代码, int g(i ...

  4. java入门--4111:判断游戏胜者-Who Is the Winner

    基础的题目 学习了StringBuilder, 通过delete来清空它 学了Map的简单用法 import java.util.*; public class Main { public stati ...

  5. nodeJs上传附件

    两种方案: 这两种方案传参还是有区别额 在nodeJs中上传附件调用了 multer 的中间件,采用这个中间件来上传 首先是表单(前端部分): <!DOCTYPE html> <ht ...

  6. 转 kvm、qemu-kvm、ibvirt及openstack,之间的关系

    KVM是最底层的hypervisor,它是用来模拟CPU的运行,它缺少了对network和周边I/O的支持,所以我们是没法直接用它的. QEMU-KVM就是一个完整的模拟器,它是构建基于KVM上面的, ...

  7. C++ STL 的底层数据结构实现

    C++ STL 的实现:   1.vector      底层数据结构为数组 ,支持快速随机访问   2.list            底层数据结构为双向链表,支持快速增删   3.deque    ...

  8. luogu2678 [NOIp2015]跳石头 (二分答案+贪心)

    先二分出一个x,我们要算使最近的跳跃距离>=x的最少移除数量是否<=M就可以了 然后就别dp了...贪心就完事了...我肯定能不移就不移比较好... #include<bits/st ...

  9. 【uoj7】 NOI2014—购票

    http://uoj.ac/problem/7 (题目链接) 题意 给出一棵有根树,每次从一个节点出发可以买票到达它的一定范围内的祖先.问对于每一个点,到达根的最小花费是多少. Solution 右转 ...

  10. 数组初始化 memset fill

    #include <cstdio> #include <cstdlib> #include <cmath> #include <cstring> #in ...