AngularJs dynamic download from response

Question

I have written a directive based on Scott's answer. You'd use it like so: ``` ``` Issue: the code below throws an error `TypeError: Invalid calling object` in `IE11` on the first method (line: `saveBlob(blob, filename);`). Even though it falls back to other methods of downloading, it is my understanding that the saveMethod1 should work in `IE11`. Here is the code: ``` 'use strict'; // directive allows to provide a function to be executed to get data to be downloaded // attributes: // download-response - Required. Function to get data. It must return a promise. It must be declared on the $scope. // download-success - Optional. Function to be executed if download-response function was successfully resolved. It must be declared on the $scope. // download-error - Optional. Funct…

Accepted Answer

Problem:

I have resolved this issue. It appears that Internet Explorer 11 does not like aliases to the `msSaveBlob` function, demonstrated by the simplest examples:

```
// Succeeds
navigator.msSaveBlob(new Blob(["Hello World"]), "test.txt");

// Fails with "Invalid calling object"
var saveBlob = navigator.msSaveBlob;
saveBlob(new Blob(["Hello World"]), "test.txt");
```

So essentially the generic alias created to encapsulate `saveBlob` functionality, which should be permissible, prevents `msSaveBlob` from working as expected:

```
var saveBlob = navigator.msSaveBlob || navigator.webkitSaveBlob || navigator.mozSaveBlob || navigator.saveBlob;
```

Workaround:

So the work around is to test for `msSaveBlob` separately.

```
if(navigator.msSaveBlob)
    navigator.msSaveBlob(blob, filename);
else {
    // Try using other saveBlob implementations, if available
    var saveBlob = navigator.webkitSaveBlob || navigator.mozSaveBlob || navigator.saveBlob;
    if(saveBlob === undefined) throw "Not supported";
    saveBlob(blob, filename);
}
```

tl;dr

So the `msSaveBlob` method works, as long as you don't alias the function. Perhaps it's a security precaution - but then perhaps a security exception would have been more appropriate, though I think it is most likely a flaw, considering the source. :)

AngularJs dynamic download from response

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