WPF图像UriSource和数据使用HTTP绑定：\\网址 [英] WPF Image UriSource and Data Binding using http:\\ URL
问题描述
我有一个WPF用户控件的Web URL显示图像的问题。我已经完成了所有工作的建议在2008年8月在本网站问过类似的问题（http://stackoverflow.com/questions/20586/wpf-image-urisource-and-data-binding），但没有这些建议已经工作
I am having a problem displaying an image with a web URL in a WPF user control. I have worked through all the suggestions for a similar problem asked on this site in Aug 2008 (http://stackoverflow.com/questions/20586/wpf-image-urisource-and-data-binding) but none of those suggestions have worked.
我想要做的是：
<Image Width="50" Name="MemberImage">
<Image.Source>
<BitmapImage DecodePixelWidth="50" UriSource="{Binding Member.ImageFilePathUri}" />
</Image.Source>
</Image>
ImageFilePathUri是一个URI通过从字符串路径中创建：
ImageFilePathUri is a Uri created from the string path through:
public Uri ImageFilePathUri
{
get
{
return new Uri(this.ImageFilePath);
}
}
}
这给出了物业 UriSource'或财产'的StreamSource'必须设置。 。错误预期。
This gives the "Property 'UriSource' or property 'StreamSource' must be set." error as expected.
我使用的是值转换器也尝试：
I have also tried using a value converter:
public class ImageConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
var image = new BitmapImage();
image.BeginInit();
if (value != null)
{
image.UriSource = new Uri((string)value);
}
image.DecodePixelWidth = 50;
image.EndInit();
return image;
}
}
不过，使用绑定到它：
However, binding to it using:
<Image Name="TestImage" Width="50" Source="{Binding Path=Member.ImageFilePath, Converter=Parliament.HansardApplicationSuite.Logging.Helpers.ImageConverter}"></Image>
不显示图像。
doesn't display the image.
进一步企图以编程方式加载图像，在控制构造函数和/或控件加载事件也没有工作：
A further attempt to load the image programmatically, in the control constructor and/or the control Loaded event have also not worked:
if (this.MemberRollItemViewModel.Member != null)
{
var image = new BitmapImage();
image.BeginInit();
image.UriSource = new Uri(this.MemberRollItemViewModel.Member.ImageFilePath);
image.DecodePixelWidth = 50;
image.EndInit();
this.MemberImage.Source = image;
}
有一件事已经工作是保存图像到本地文件路径和显示该：
The one thing that has worked is saving the image to a local file path and displaying that:
<Image Width="50" Name="MemberImage">
<Image.Source>
<BitmapImage DecodePixelWidth="50" UriSource="C:\Data\6bc64e7b-2df5-40d5-b6c4-eaf732318222.jpg" />
</Image.Source>
</Image>
这显然是只在调试问题有用的，而不是一个解决方案。 。相同的代码，但用HTTP地址为本地文件路径行不通
This is obviously only useful in debugging the problem and is not a solution. The same code but substituting the http address for the local file path doesn't work.
<Image.Source>
<BitmapImage DecodePixelWidth="50" UriSource="http://member.org/6bc64e7b-2df5-40d5-b6c4-eaf732318222.jpg" />
</Image.Source>
更新：
Update:
这是MemberImage属性实现。
This is the MemberImage property implementation.
public BitmapImage MemberImage
{
get
{
var image = new BitmapImage();
if (this.Member != null)
{
WebRequest request = WebRequest.Create(new Uri(this.Member.ImageFilePath, UriKind.Absolute));
request.Timeout = -1;
WebResponse response = request.GetResponse();
Stream responseStream = response.GetResponseStream();
BinaryReader reader = new BinaryReader(responseStream);
MemoryStream memoryStream = new MemoryStream();
byte[] bytebuffer = new byte[BytesToRead];
int bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
while (bytesRead > 0)
{
memoryStream.Write(bytebuffer, 0, bytesRead);
bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
}
image.BeginInit();
memoryStream.Seek(0, SeekOrigin.Begin);
image.StreamSource = memoryStream;
image.EndInit();
}
return image;
}
}
更新：
Update:
这是我如何绑定到我的视图控件：
This is how I am binding to the control in my view:
<Image Width="50" Source="{Binding MemberImage}" />
MemberImage是我上面已经给出了财产。我的数据上下文被设置正确，因为该属性正在运行，它只是不返回的图像。
MemberImage is the property I have given above. My data context is being set correctly because that property is being run, it's just not returning an image.
推荐答案
WEBURL不能作为源来的BitmapImage的UriSource属性来提供。如果你需要在本地下载图像并绑定该路径来UriSource WEBURL。请参见下面的
WebURL can't be provided as a source to UriSource property of BitmapImage. If it is weburl you need to download that image locally and bind that path to UriSource. See the below
更新：
void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
var image = new BitmapImage();
int BytesToRead=100;
WebRequest request = WebRequest.Create(new Uri("http://www.interweb.in/attachments/pc-wallpapers/16187d1222942178-nature-wallpaper-nature-summer-wallpaper.jpg", UriKind.Absolute));
request.Timeout = -1;
WebResponse response = request.GetResponse();
Stream responseStream = response.GetResponseStream();
BinaryReader reader = new BinaryReader(responseStream);
MemoryStream memoryStream = new MemoryStream();
byte[] bytebuffer = new byte[BytesToRead];
int bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
while (bytesRead > 0)
{
memoryStream.Write(bytebuffer, 0, bytesRead);
bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
}
image.BeginInit();
memoryStream.Seek(0, SeekOrigin.Begin);
image.StreamSource = memoryStream;
image.EndInit();
myImage.Source = image;
}
这篇关于WPF图像UriSource和数据使用HTTP绑定：\\网址的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
