xcode 如何将 JSON 响应保存到可从 UIWebWiew 中加载的本地 HTML 文件中访问的文件
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How can I save a JSON response to a file that would be accessible from within a local HTML file loaded inside UIWebWiew
提问by Dustin Carpenter
I am receiving a JSON response and am currenlty able to make use of the data within my app.
我收到了一个 JSON 响应，并且目前可以使用我的应用程序中的数据。
I would like to save this response to a file so I could reference within an JS file located inside my project. I have already requested this data once when the application is launched so why not save it to a file and reference that throughout so only one call is needed for the data.
我想将此响应保存到文件中，以便我可以在位于我的项目内的 JS 文件中进行引用。我已经在应用程序启动时请求过一次这些数据，所以为什么不将它保存到一个文件中并在整个过程中引用它，这样数据只需要一次调用。
The HTML files for my UIWebView are imported into my Xcode project using the "create folder reference" option and the path to my JS file is html->js->app.js
我的 UIWebView 的 HTML 文件使用“创建文件夹引用”选项导入到我的 Xcode 项目中，我的 JS 文件的路径是 html->js->app.js
I want to save the response as data.jsonsomewhere on the device and then reference inside my js file like this request.open('GET', 'file-path-to-saved-json.data-file', false);
我想将响应保存在data.json设备上的某个地方，然后像这样在我的 js 文件中引用request.open('GET', 'file-path-to-saved-json.data-file', false);
How can I achieve this?
我怎样才能做到这一点？
回答by Dustin Carpenter
After working with the idea some more here is what I came up with.
在研究了这个想法之后，我想到了更多。
When the application is installed there is a default data file in the package that I copy to the Documents folder. When the application didFinishLaunchingWithOptionsruns I call the following method:
安装应用程序后，包中有一个默认数据文件，我将其复制到 Documents 文件夹中。当应用程序didFinishLaunchingWithOptions运行时，我调用以下方法：
- (void)writeJsonToFile
{
//applications Documents dirctory path
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//live json data url
NSString *stringURL = @"http://path-to-live-file.json";
NSURL *url = [NSURL URLWithString:stringURL];
NSData *urlData = [NSData dataWithContentsOfURL:url];
//attempt to download live data
if (urlData)
{
NSString *filePath = [NSString stringWithFormat:@"%@/%@", documentsDirectory,@"data.json"];
[urlData writeToFile:filePath atomically:YES];
}
//copy data from initial package into the applications Documents folder
else
{
//file to write to
NSString *filePath = [NSString stringWithFormat:@"%@/%@", documentsDirectory,@"data.json"];
//file to copy from
NSString *json = [ [NSBundle mainBundle] pathForResource:@"data" ofType:@"json" inDirectory:@"html/data" ];
NSData *jsonData = [NSData dataWithContentsOfFile:json options:kNilOptions error:nil];
//write file to device
[jsonData writeToFile:filePath atomically:YES];
}
}
Then throughout the application when I need to reference the data, I use the saved file.
然后在整个应用程序中，当我需要引用数据时，我会使用保存的文件。
//application Documents dirctory path
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSError *jsonError = nil;
NSString *jsonFilePath = [NSString stringWithFormat:@"%@/%@", documentsDirectory,@"data.json"];
NSData *jsonData = [NSData dataWithContentsOfFile:jsonFilePath options:kNilOptions error:&jsonError ];
To reference the json file in my JS code, I added a URL parameter for "src" and passed the file path to the Applications Documents folder.
为了在我的 JS 代码中引用 json 文件，我为“src”添加了一个 URL 参数，并将文件路径传递给 Applications Documents 文件夹。
request.open('GET', src, false);
