是否可以通过编程方式将文件(即 sqlite 数据库文件)从 Internet 下载到您的 iPhone 应用程序中以供以后在应用程序中使用?
我正在尝试使用 NSURLConnection
,但无法保存文件。
这是我正在尝试的示例代码:
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *file = [NSString stringWithFormat:@"http://en.wikipedia.org/wiki/Text_file"];
NSURL *fileURL = [NSURL URLWithString:file];
NSURLRequest *req = [NSURLRequest requestWithURL:fileURL];
NSURLConnection *conn = [NSURLConnection connectionWithRequest:req delegate:self];
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[self.fileData setLength:0];
self.totalFileSize = [NSNumber numberWithLongLong:[response expectedContentLength]];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[self.fileData appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSArray *dirArray = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSLog(@"%@", [dirArray objectAtIndex:0]);
NSString *path = [NSString stringWithFormat:@"%@/blah.text", [dirArray objectAtIndex:0]];
if ([self.fileData writeToFile:path options:NSAtomicWrite error:nil] == NO) {
NSLog(@"writeToFile error");
}
else {
NSLog(@"Written!");
}
}
最佳答案
什么是文件数据?它是如何定义和初始化的?
fileData = [NSMutableData data];
应该在某处之后:
NSURLConnection *conn = [NSURLConnection connectionWithRequest:req delegate:self];
您必须根据内存管理规则初始化 fileData 并保留它。
试试看我的回答。有用!
关于ios - 从url下载文件并保存到iPhone上的资源,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/2102267/