小编Tem*_*ple的帖子

我有一个输入csv文件,其中的列包含类似于以下示例的信息:

805265
995874
805674
984654
332574
339852

我想基于前2个字符将唯一值提取到数组中,因此使用上面的示例我的结果将是:

80,99,98,33

我如何使用PowerShell实现这一目标？

我有一些类似的代码:

HttpWebRequest req;
HttpWebResponse response;
Stream receiveStream = null;
StreamReader readStream = null;
try
{
    req = (HttpWebRequest)WebRequest.Create("someUrl"));
    req.Credentials = CredentialCache.DefaultCredentials;

    req.Method = "GET";

    response = (HttpWebResponse)req.GetResponse();
    receiveStream = response.GetResponseStream();
    readStream = new StreamReader(receiveStream, Encoding.Default);

    return readStream.ReadToEnd();
}
catch
{
    return "Error";
}
finally 
{
    readStream = null;
    receiveStream = null;
    response = null;
    req = null;
}

此代码是否应该具有readStream.Dispose()和responseStream.Dispose()而不是将它们都设置为null？

在 iOS13 发布之后，我正在使用 Cordova 测试混合应用程序。启动相机非常慢，并生成以下内容：

================================================== ================

主线程检查器：在后台线程上调用的 UI API：-[UIImagePickerController init]

PID：1347，TID：618928，线程名称：（无），队列名称：com.apple.root.default-qos，QoS：0

回溯：

4 0x0000000100f1bba0 +[CDVCameraPicker createFromPictureOptions:] + 124

5 0x0000000100f15d54 -[CDVCamera showCameraPicker:withOptions:] + 108

6 0x0000000100f15570 __25-[CDVCamera takePicture:]_block_invoke_2 + 336

7 AVFoundation 0x00000001b76178f8 2BC0C357-314E-3AE8-B006-C28528B87512 + 710904

8 TCC 0x00000001b35dfbf8 85A762AF-99DB-3B4C-B24B-09600CC17196 + 7160

9 TCC 0x00000001b35e3de4 85A762AF-99DB-3B4C-B24B-09600CC17196 + 24036

10 libxpc.dylib 0x00000001acfe3804 79A1F1AD-9CB4-3334-91D9-E1ED6B1032A3 + 104452

11 libxpc.dylib 0x00000001acfd72c4 79A1F1AD-9CB4-3334-91D9-E1ED6B1032A3 + 53956

12 libdispatch.dylib 0x000000010109b3b4 _dispatch_client_callout3 + 20

13 libdispatch.dylib 0x00000001010b7000 _dispatch_mach_msg_async_reply_invoke + 392

14 libdispatch.dylib 0x00000001010ada8c _dispatch_kevent_worker_thread + 1436

15 …