我想从html文件中的按钮通知我的网页视图并触发javascript:
function notify(str) {
window.external.notify(str);
}
使用wv_ScriptNotify(..., ...)
捕获的事件:
void wv_ScriptNotify(object sender, NotifyEventArgs e)
{
Color c=Colors.Red;
if (e.CallingUri.Scheme =="ms-appx-web" || e.CallingUri.Scheme == "ms-appdata")
{
if (e.Value.ToLower() == "blue") c = Colors.Blue;
else if (e.Value.ToLower() == "green") c = Colors.Green;
}
appendLog(string.Format("Response from script at '{0}': '{1}'", e.CallingUri, e.Value), c);
}
我在ms-appx-web
上设置了html文件并且运行良好,我意识到html文件必须存储到本地文件夹中。因此,我将ms-appx-web:///.../index.html
更改为ms-appdata:///local/.../index.html
。
已经在microsoft论坛中搜索并获得this。在该线程上有一个使用解析器的解决方案,但我仍然感到困惑,它如何通过javascript通知,如使用window.external.notify
? C#方面的哪种事件会从“ScriptNotify”以外的javascript中捕获“通知”?
here有一个解决方案,例如使用解析程序,它说使用ms-local-stream://
而不是使用ms-appdata://local
,所以我仍然可以使用ScriptNotify
事件。但不幸的是,使用ms-appx
的示例意味着使用InstalledLocation
而不是LocalFolder
。
尝试使用Google搜索并在msdn网站中搜索ms-local-stream
的文档,但唯一的文档只是ms-local-stream
的格式,没有像ms-local-stream://appname_KEY/folder/file
这样的示例。< / p>
根据该文档,我做了一些样本来尝试:
public sealed class StreamUriWinRTResolver : IUriToStreamResolver
{
/// <summary>
/// The entry point for resolving a Uri to a stream.
/// </summary>
/// <param name="uri"></param>
/// <returns></returns>
public IAsyncOperation<IInputStream> UriToStreamAsync(Uri uri)
{
if (uri == null)
{
throw new Exception();
}
string path = uri.AbsolutePath;
// Because of the signature of this method, it can't use await, so we
// call into a separate helper method that can use the C# await pattern.
return getContent(path).AsAsyncOperation();
}
/// <summary>
/// Helper that maps the path to package content and resolves the Uri
/// Uses the C# await pattern to coordinate async operations
/// </summary>
private async Task<IInputStream> getContent(string path)
{
// We use a package folder as the source, but the same principle should apply
// when supplying content from other locations
try
{
// My package name is "WebViewResolver"
// The KEY is "MyTag"
string scheme = "ms-local-stream:///WebViewResolver_MyTag/local/MyFolderOnLocal" + path; // Invalid path
// string scheme = "ms-local-stream:///WebViewResolver_MyTag/MyFolderOnLocal" + path; // Invalid path
Uri localUri = new Uri(scheme);
StorageFile f = await StorageFile.GetFileFromApplicationUriAsync(localUri);
IRandomAccessStream stream = await f.OpenAsync(FileAccessMode.Read);
return stream.GetInputStreamAt(0);
}
catch (Exception) { throw new Exception("Invalid path"); }
}
}
在我的MainPage.xaml.cs中:
protected override void OnNavigatedTo(NavigationEventArgs e)
{
// The 'Host' part of the URI for the ms-local-stream protocol needs to be a combination of the package name
// and an application-defined key, which identifies the specific resolver, in this case 'MyTag'.
Uri url = wv.BuildLocalStreamUri("MyTag", "index.html");
StreamUriWinRTResolver myResolver = new StreamUriWinRTResolver();
// Pass the resolver object to the navigate call.
wv.NavigateToLocalStreamUri(url, myResolver);
}
当它到达StorageFile f = await StorageFile.GetFileFromApplicationUriAsync(localUri);
行时总是会出现异常。
如果有人遇到这个问题并且已经解决了,请告知。
答案 0 :(得分:7)
调试完成后,我发现了一些有趣的内容,BuildLocalStreamUri
部分已经自动生成ms-local-stream
。
我对getContent
类中的StreamUriWinRTResolver
方法进行了一些更改:
public sealed class StreamUriWinRTResolver : IUriToStreamResolver
{
/// <summary>
/// The entry point for resolving a Uri to a stream.
/// </summary>
/// <param name="uri"></param>
/// <returns></returns>
public IAsyncOperation<IInputStream> UriToStreamAsync(Uri uri)
{
if (uri == null)
{
throw new Exception();
}
string path = uri.AbsolutePath;
// Because of the signature of this method, it can't use await, so we
// call into a separate helper method that can use the C# await pattern.
return getContent(path).AsAsyncOperation();
}
/// <summary>
/// Helper that maps the path to package content and resolves the Uri
/// Uses the C# await pattern to coordinate async operations
/// </summary>
private async Task<IInputStream> getContent(string path)
{
// We use a package folder as the source, but the same principle should apply
// when supplying content from other locations
try
{
// Don't use "ms-appdata:///" on the scheme string, because inside the path
// will contain "/local/MyFolderOnLocal/index.html"
string scheme = "ms-appdata://" + path;
Uri localUri = new Uri(scheme);
StorageFile f = await StorageFile.GetFileFromApplicationUriAsync(localUri);
IRandomAccessStream stream = await f.OpenAsync(FileAccessMode.Read);
return stream.GetInputStreamAt(0);
}
catch (Exception) { throw new Exception("Invalid path"); }
}
}
更改MainPage.xaml.cs上的文件路径:
protected override void OnNavigatedTo(NavigationEventArgs e)
{
// The 'Host' part of the URI for the ms-local-stream protocol needs to be a combination of the package name
// and an application-defined key, which identifies the specific resolver, in this case 'MyTag'.
Uri url = wv.BuildLocalStreamUri("MyTag", "/local/MyFolderOnLocal/index.html");
StreamUriWinRTResolver myResolver = new StreamUriWinRTResolver();
// Pass the resolver object to the navigate call.
wv.NavigateToLocalStreamUri(url, myResolver);
wv.ScriptNotify += wv_ScriptNotify;
}
protected override void wv_ScriptNotify(object sender, NavigationEventArgs e)
{
if (e.CallingUri.Scheme == "ms-local-stream")
{
// Do your work here...
}
}