<分区>
我正在尝试将文件列表复制到目录中。我正在使用异步/等待。 但是我遇到了这个编译错误
The 'await' operator can only be used within an async lambda expression. Consider marking this lambda expression with the 'async' modifier.
我的代码是这样的
async Task<int> CopyFilesToFolder(List<string> fileList,
IProgress<int> progress, CancellationToken ct)
{
int totalCount = fileList.Count;
int processCount = await Task.Run<int>(() =>
{
int tempCount = 0;
foreach (var file in fileList)
{
string outputFile = Path.Combine(outputPath, file);
await CopyFileAsync(file, outputFile); //<-- ERROR: Compilation Error
ct.ThrowIfCancellationRequested();
tempCount++;
if (progress != null)
{
progress.Report((tempCount * 100 / totalCount)));
}
}
return tempCount;
});
return processCount;
}
private async Task CopyFileAsync(string sourcePath, string destinationPath)
{
using (Stream source = File.Open(sourcePath, FileMode.Open))
{
using (Stream destination = File.Create(destinationPath))
{
await source.CopyToAsync(destination);
}
}
}
谁能指出我在这里遗漏了什么？