I am working on developing a file upload feature and I'm in need of validation specifically for Excel files. The structure of my form is as follows:
<div class="row">
<input type="hidden" name="key" value="uploads/${filename}">
<table class="content-centered">
<tr>
<td><input type="file" file-model="imageToUpload" data-rule-required="true"
accept="application/vnd.ms-excel" /></td>
<td><span ng-class="{errorMessage: fileStatus.status == false,
regularMessage: fileStatus.status == true}">  {{fileStatus.message}}
</span>
</td>
</tr>
</table>
<div class="centered" style="margin-top: 12px;">
<div ng-click='imageUpload()' class="btn blueBtn">Upload
<span class="glyphicon glyphicon-upload"></span>
</div>
<div ng-click='$close()' class="btn orgBtn">Close</div>
</div>
</div>
I have tried using data-rule-required="true" and accept="application/vnd.ms-excel" for validation, but unfortunately it did not work as expected. Does anyone have insights on how file validation works in AngularJS?