具有不同文件格式的Scanf功能 [英] Scanf function for different file format

问题描述

大家好，
这个问题是我以前发布的问题的一部分: [ ^ ]]，但这尤其与swscanf_s函数有关.

在代码中:

Hello All,
This question is a part of the question I had previously posted:[Inconsistent file format[^]] , but this is particularly about swscanf_s function.

In the code :

CStdioFile std;
CString    buffer;
wchar_t str1[2046],str2[2046],str3[2046],str4[2046],str5[2046],str6[2046];
double time, lat;
if (std.Open(fname, CFile::modeRead)) // CStdioFile csf;
{
  while (std.ReadString(buffer) )
  {
    int out = 0;
  out = swscanf_s(buffer, (_T("%[^,],%lf,%lf,%[^,],%lf,%[^,],%d,%d,%lf,%lf,%[^,],%lf,%[^,],,%[^,]"),
 // str1, 2046, &sTime, &db1,str2,2046,&db2,str3,2046,&in1,&in2,&db3,&db4,str4,2046,&db5,str5,2046,str6,2046);
  if(out = 15)
  {
   //calculations
  }
  else
   //output the error buffer lines
  }

由于文件的格式不一定总是相同的，因此某些文件的变量可能不超过3个.因此，我使用了一种在swscanf_s中使用的方法，以便它返回一个字符串.

即;

Since the file is not always of the same format, some files may have more than 3 variable or less. So I used a method to use in the swscanf_s, such that it returns a string.

i.e;

SetValues()
{
  wchar_t str1[2046];
  double time, lat; 
  CString  fmtStr;
  fmtStr.AppendFormat((_T("%[^,],%lf,%lf,%[^,],%lf,%[^,],%d,%d,%lf,%lf,%[^,],%lf,%[^,],,%[^,]"),
   // str1, 2046, &sTime, &db1,str2,2046,&db2,str3,2046,&in1,&in2,&db3,&db4,str4,2046,&db5,str5,2046,str6,2046));  
  return fmtStr;
}

并在swscanf_s函数中使用此函数.像这样:

And use this function in the swscanf_s function. Like this :

out = swscanf_s(buffer, SetValues();

但是我收到一条错误消息:

But I get an error that says:

Expression: ("Incorrect Format specifier", 0)

输入文件格式如下所示:$ GPS1,145217.00,7434.7369647，N，05713.8922390，W，2,09,0.9,44.94，M，21.98，M，43.2,0081 * 55
需要一些帮助

The input file format looks like this: $GPS1,145217.00,7434.7369647,N,05713.8922390,W,2,09,0.9,44.94,M,21.98,M,43.2,0081*55
Need some help please

推荐答案

GPS1,145217.00,7434.7369647，N，05713.8922390，W，2,09,0.9,44.94，M，21.98，M，43.2,0081 * 55
需要一些帮助

GPS1,145217.00,7434.7369647,N,05713.8922390,W,2,09,0.9,44.94,M,21.98,M,43.2,0081*55
Need some help please

问题不在于文件格式的内容！错误消息告诉yu到底是什么问题:格式说明符不一致！您应该打印出SetValues()的返回值.很明显，它返回的字符串不是格式字符串，您在SetValues()内确实做了一些奇怪的事情.请注意，您正在使用已格式化的字符串作为另一个函数调用中的格式字符串:因此，在原始格式字符串中，如果希望在格式化时将其作为单个的％"，则应使用双％"字符下次.示例:

The problem is not with the conents of the file format! The error message tells yu exactly what the problem is: Inconsistent Format Specifier! You should print out the return value of SetValues(). Its pretty clear that it returns a string that isn''t a format string, you do something realy weird inside SetValues(). Note that you are using an already formatted string as a format string in another function call: so in your original format string you should use double ''%'' character if you want that to be a single ''%'' when you format next time. Example:

CString s;
s.Format("%%0%dd", 9);
CString t;
t.Format((const char*)s, 1);

在第一个格式字符串中，％d为实数格式说明符，并使用双精度''％:" %% 0 ％d d"，因此结果为"％09d"，它将是下一个格式操作的有效格式字符串.有双重的％"把戏吗?

In the first format string the %d is a real format specifier and the double ''%'': "%%0%dd" so the result will be "%09d" that will be a valid format string for the next format operation. Got the double ''%'' trick?

您正在使用of脚的Microsoft类和C运行时函数的组合，这些类只能在STL到来之前使用.我的总体建议是使用适当的C ++. CString是垃圾，CStdioFile更糟.

您的错误与您要传入的字符串的格式有关，因此我们可能需要查看您正在执行的C函数调用的输入(即使您要使用C，该函数也已过时)，知道出了什么问题.

You are using a combination of crappy Microsoft classes that were only meant to be used until the STL arrived, and C runtime functions. My overall recommendation is to use proper C++. CString is rubbish and CStdioFile is worse.

Your error relates to the format of the string you''re passing in, so we probably need to see the inputs to the C function call you''re making ( which is also deprecated, even if you want to use C ), to know what is going wrong.

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