Progress info using HttpClient

问题

I wanted to implement progress bar using 'Windows.Web.Http.HttpClient' in Windows Phone 8.1 Silverlight.

Edit: First Attempt:

private async Task CheckProgress()
{
    var df = httpClient.GetAsync(new Uri(uriString, UriKind.Absolute)).Progress = Progress;

    // here i want to stop the execution till whole content downloaded

    // Reason to wait here
    // this client download will be used by one more async method. so i need to wait here till the file completely downloaded.

    // this whole is done in this method only ( requirement)
} 

private void  Progress(IAsyncOperationWithProgress<HttpResponseMessage, HttpProgress> asyncInfo, HttpProgress progressInfo)
{
   // here i getting the progress value.
   // i have already set a call back method that report the progress on the UI.
}

One more attempt: But getting the Exception Invocation of delegate at wrong time.

private async Task CheckProgress()
{
    var df = httpClient.GetAsync(new Uri(uriString, UriKind.Absolute))

    df.Progress =  Progress;

    await df;
    // here i want to stop the execution till whole content downloaded
} 

Question:

All, I wanted is to stop the CheckProgress() Method to keep waiting till the whole download completed.

回答1:

I got the solution of my problem but it is just a little miss in my Second Attempt.

private async Task CheckProgress()
{
    var df = httpClient.GetAsync(new Uri(uriString, UriKind.Absolute))

    df.Progress = (res, progress) =>
    { 
       // no separate event handler.
    }

    await df;   
} 

It is just working fine. Hope it will help someone cheers:)

来源：https://stackoverflow.com/questions/24827009/progress-info-using-httpclient