How do you store a file locally using Apache Cordova 3.4.0

问题

I am having a problem storing a file locally on an iOS (or android) device using apache cordova's "file" plugin. The problem I believe is setting the path properly.

this is the error message I get from Xcode Could not create path to save downloaded file: The operation couldn\U2019t be completed. (Cocoa error 512.)

Here is the code where I am attempting to save the file locally:

<script type="text/javascript" charset="utf-8" src="cordova.js"></script>
<script type="text/javascript" charset="utf-8">


document.addEventListener("deviceready", onDeviceReady, false);

var root;


function onDeviceReady(){
    // Note: The file system has been prefixed as of Google Chrome 12:
    window.requestFileSystem  = window.requestFileSystem || window.webkitRequestFileSystem;
    window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, onInitFs, errorHandler);
}

function onInitFs(fs) {


    var fileURL = "cdvfile://localhost/persistant/file.png";

    var fileTransfer = new FileTransfer();
    var uri = encodeURI("http://upload.wikimedia.org/wikipedia/commons/6/64/Gnu_meditate_levitate.png");

    fileTransfer.download(
            uri,
            fileURL,
            function(entry) {
                console.log("download complete: " + entry.fullPath);
            },
            function(error) {
                console.log("download error source " + error.source);
                console.log("download error target " + error.target);
                console.log("upload error code" + error.code);
            },
            false,
            {
                headers: {
                    "Authorization": "Basic dGVzdHVzZXJuYW1lOnRlc3RwYXNzd29yZA=="
                }
            }
    );
}


function errorHandler(e) {
  var msg = '';

  switch (e.code) {
    case FileError.QUOTA_EXCEEDED_ERR:
      msg = 'QUOTA_EXCEEDED_ERR';
      break;
    case FileError.NOT_FOUND_ERR:
      msg = 'NOT_FOUND_ERR';
      break;
    case FileError.SECURITY_ERR:
      msg = 'SECURITY_ERR';
      break;
    case FileError.INVALID_MODIFICATION_ERR:
      msg = 'INVALID_MODIFICATION_ERR';
      break;
    case FileError.INVALID_STATE_ERR:
      msg = 'INVALID_STATE_ERR';
      break;
    default:
      msg = 'Unknown Error';
      break;
  };

  alert('Error: ' + msg);
}

</script>

回答1:

Your file path contains a typo (or a grammar error):

var fileURL = "cdvfile://localhost/persistant/file.png";

You should write it as persistent.

Correct code:

var fileURL = "cdvfile://localhost/persistent/file.png";

回答2:

Check out these links :

http://cordova.apache.org/docs/en/3.4.0/cordova_plugins_pluginapis.md.html#Plugin%20APIs https://github.com/apache/cordova-plugin-file/blob/dev/doc/index.md

http://cordova.apache.org/docs/en/3.0.0/cordova_file_file.md.html#File

First and second links provide you information about the plugin File and how to install it.

The third one show you how to use the File plugin.

Everytime you need to do something with Cordova, check if a plugin is available to do it :)

regards.

回答3:

So far I have only tested this on Android, but I believe it should work as-is, or with little modification on IOS:

var url = 'example.com/foo'

window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function(fileSystem){
    fileSystem.root.getFile('foo_file', {create: true, exclusive: false},
        function(file_entry){
            var ft = new FileTransfer()
            ft.download(url, file_entry.toURL(), function(fe){
                fe.file(function(f){
                    reader = new FileReader()
                    reader.onloadend = function(ev){
                        console.log('READ!', ev.target.result)
                    }
                    reader.readAsText(f)
                })
            })
        }
    )
})

Note that I also needed the contents of the file, so the bit at the end may be omitted if you don't need the contents at the time of downloading.

Also note that there is a far simpler method using window.saveAs but it's only available in Android 4.4.

来源：https://stackoverflow.com/questions/22336352/how-do-you-store-a-file-locally-using-apache-cordova-3-4-0