Silverlight跨线程ui更新问题
我有这门课:Silverlight跨线程ui更新问题,silverlight,multithreading,Silverlight,Multithreading,我有这门课: public class UploadFile : INotifyPropertyChanged { private string name; public string Name { get { return name; } set { name = value; OnPropertyChanged("Name"); }
public class UploadFile : INotifyPropertyChanged {
private string name;
public string Name {
get {
return name;
}
set {
name = value;
OnPropertyChanged("Name");
}
}
private FileInfo fileInfo;
public FileInfo FileInfo { get; set; }
private string length;
public string Length {
get {
return length;
}
set {
length = value;
OnPropertyChanged("Length");
}
}
private int percentage;
public int Percentage {
get {
return percentage;
}
set {
percentage = value;
OnPropertyChanged("Percentage");
}
}
public string ProgressValue {
get { return string.Format("{0}%", Percentage); }
}
private string imageSource;
public string ImageSource {
get {
return imageSource;
}
set {
imageSource = value;
OnPropertyChanged("ImageSource");
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
#endregion
private void OnPropertyChanged(string property) {
if (PropertyChanged != null) {
PropertyChanged(this, new PropertyChangedEventArgs(property));
}
}
}
我正在尝试创建一个能够进行大型和多个文件上载的文件上载。我正在使用一个web服务来完成这项工作。我在我的UI中做了一个双向绑定,现在我想上传文件。我用这个代码来做这件事
private void DoUpload() {
foreach (UploadFile file in fileInfos){
int BUFFERSIZE = 1024;
int offset = 0; //get from webservice, when partial file
FileStream s = file.FileInfo.OpenRead();
byte[] buffer = null;
long remainingBytes = s.Length - offset;
while (remainingBytes > 0) {
if (remainingBytes < BUFFERSIZE) {
buffer = new byte[remainingBytes];
BUFFERSIZE = (int)remainingBytes;
}
else if (remainingBytes > BUFFERSIZE) {
buffer = new byte[BUFFERSIZE];
}
s.Read(buffer, 0, BUFFERSIZE);
//push to webservice
Thread.Sleep(20);
//UploadService.Service1SoapClient client = new MultiLargeFileUpload.UploadService.Service1SoapClient();
//client.LargeUploadCompleted +=new EventHandler<AsyncCompletedEventArgs>(client_LargeUploadCompleted);
//client.LargeUploadAsync(1, buffer, file.Name);
offset += BUFFERSIZE;
int newPercentage = offset / (int)file.FileInfo.Length * 100;
file.Percentage = newPercentage;
remainingBytes = s.Length - offset;
}
//file.Percentage = 100;
//file.ImageSource = "accept.png";
}
}
private void DoUpload(){
foreach(在fileInfos中上载文件){
int BUFFERSIZE=1024;
int offset=0;//从webservice获取部分文件时
FileStream s=file.FileInfo.OpenRead();
字节[]缓冲区=空;
long remainingBytes=s.长度-偏移量;
而(剩余字节数>0){
if(剩余字节数<缓冲区大小){
缓冲区=新字节[剩余字节];
BUFFERSIZE=(int)剩余字节数;
}
else if(remainingBytes>BUFFERSIZE){
buffer=新字节[BUFFERSIZE];
}
s、 读取(缓冲区,0,缓冲区大小);
//推送到Web服务
睡眠(20);
//UploadService.Service1SoapClient=new MultiLargeFileUpload.UploadService.Service1SoapClient();
//client.LargeUploadCompleted+=新事件处理程序(client\u LargeUploadCompleted);
//LargeUploadAsync(1,buffer,file.Name);
偏移量+=缓冲区大小;
int newPercentage=offset/(int)file.FileInfo.Length*100;
file.Percentage=newPercentage;
remainingBytes=s.长度-偏移量;
}
//百分比=100;
//file.ImageSource=“accept.png”;
}
}
问题是我无法更新UI或跨线程操作。我尝试使用Dispatcher,但没有成功,因为我不知道在哪里插入它。我猜您正在尝试在中更新UI
file.Percentage = newPercentage;
remainingBytes = s.Length - offset;
您必须将其包装在委托中,并在此基础上执行Dispatcher.BeginInvoke以从另一个线程更新您的UI:
Dispatcher.BeginInvoke(()=>{
file.Percentage=newPercentage;
remainingBytes = s.Length - offset;
});
通过这种方式,您可以向主线程上的messagequeue发送消息,主线程可以在有时间时执行委托