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问题 I tried to play with Strawberry Perl, and one of the things that stumped me was reading the files. I tried to do: open(FH, "D:\test\numbers.txt"); But it can not find the file (despite the file being there, and no permissions issues). An equivalent code (100% of the script other than the filename was identical) worked fine on Linux. 回答1: As per Perl FAQ 5, you should be using forward slashes in your DOS/Windows filenames (or, as an alternative, escaping the backslashes). Why can't I use "C:

问题 I tried to play with Strawberry Perl, and one of the things that stumped me was reading the files. I tried to do: open(FH, "D:\test\numbers.txt"); But it can not find the file (despite the file being there, and no permissions issues). An equivalent code (100% of the script other than the filename was identical) worked fine on Linux. 回答1: As per Perl FAQ 5, you should be using forward slashes in your DOS/Windows filenames (or, as an alternative, escaping the backslashes). Why can't I use "C:

问题 I tried to play with Strawberry Perl, and one of the things that stumped me was reading the files. I tried to do: open(FH, "D:\test\numbers.txt"); But it can not find the file (despite the file being there, and no permissions issues). An equivalent code (100% of the script other than the filename was identical) worked fine on Linux. 回答1: As per Perl FAQ 5, you should be using forward slashes in your DOS/Windows filenames (or, as an alternative, escaping the backslashes). Why can't I use "C:

问题 In below code , i'm trying to create a txt file and there i want to add some list of values. So here my approach is create a new file if file is not present and add the respective elements into it. Please see below , i'm unable to get my expected output, So can you help me with some idea so it will be very helpful public class MyTest { public static void main(String[] args) throws Exception { // TODO Auto-generated method stub SftpConn sftp = new SftpConn(); //sftp.sftpGetConnect(); List

问题 So, I read a string using cin.getline(str,10,'h') where as you can see I have used a custom delimiter 'h' and want to read a maximum of 9 characters. After doing this, I use cin>>n to read an integer into my int variable n. #include <iostream> using namespace std; int main() { int n; char str[100]; cin.getline(str, 10, 'h'); cout<<str<<'-'<<endl; cout<<"Enter a number:"; cin>>n; cout<<n; return 0; } Suppose I pass the following input 2 3 pl32 which is a '\n' followed by "2 3 pl32". I expect

问题 One of the ancient anti-pattern is people checking error status and then returning fairly useless messages like "operation failed" instead of "operation failed because ...". I want C++ file I/O operations to fail with exception and get the error message on why it failed. Specifically I want ofstream object to raise exception when file creation fails and get bit more useful message such as "permission denied" or "No file or path". This is trivial to do in languages such as C# or Java or Python

问题 Never learnt to work with streams for reading / writing data, instead I'm using the old Pascal way. Now everybody says this is not efficient and I would like to learn the file stream way, but can't really work with the tutorials that are available. I am using Excel to create and manage datasets (big data tables with one or two headers). I save these as *.txt files (tab delimited). These files I read with Delphi to fill my records and arrays, etc. Below a simplified code example of what I am

问题 in Java, suppose I have a text file with n rows, is it possible to only write and replace row x? or do I rewrite all the rows in order to edit any row? It seems that I have use RandomAccess File to read x-1 lines, and then call f.writeChars(str+"\n"); would this work? but also it won't delete the existing xth line.. 回答1: If you're not changing the line length, you can simply overwrite the original data. If you need to change the line length, or add (or remove) a row in the middle of the file,

问题 I need to send an Object from client to server by serializing it. This is my code: HttpURLConnection con = null; ObjectOutputStream out = null; ObjectInputStream inputStream = null; URL servlet = new URL("MY_URL"); con = (HttpURLConnection) servlet.openConnection(); con.setDoInput(true); con.setDoOutput(true); con.setUseCaches(false); con.setDefaultUseCaches(false); con.setRequestProperty("Content-type", "application/octet-stream"); con.setRequestMethod("POST"); out = new ObjectOutputStream

问题 I am trying to make a program that would open a file based on the users input. Here`s my code: #include <iostream> #include <fstream> #include <string> using namespace std; int main() { string filename; ifstream fileC; cout<<"which file do you want to open?"; cin>>filename; fileC.open(filename); fileC<<"lalala"; fileC.close; return 0; } But when I compile it, it gives me this error: [Error] no match for 'operator<<' (operand types are 'std::ifstream {aka std::basic_ifstream<char>}' and 'const