C + + writes data to. txt file reading data from. txt file string split __c++

Source: Internet
Author: User

Write data to a. txt file

Writes data to a. txt file
	vector<point2f> quad_pts;
	Quad_pts.push_back (point2f ( -602.935, 464.887));
	Quad_pts.push_back (point2f ( -401.548, 477.997));
	Quad_pts.push_back (point2f ( -1346.625, 261.575));
	Quad_pts.push_back (point2f ( -129.836, 283.220));

	Ofstream F1 ("Points.txt");//#include <fstream>
	char savepoints[100];//character array
	strcpy_s (savepoints, " Quad_pts ");
	F1 << savepoints << Endl;
	for (int i = 0; i < quad_pts.size (); i++)
		sprintf_s (savepoints, "px%fy%f", quad_pts[i].x, QUAD_PTS[I].Y); C12/>f1 << savepoints << Endl;

To read the. txt file data into C + +

Read data from. txt
	ifstream myFile;
	Myfile.open ("Points.txt");
	Char output[100];
	if (Myfile.is_open ()) 
		(!myfile.eof ()) 
			myFile >> output;
			cout << output << Endl;
	Myfile.close ();

Gets the part string between the two tag strings

std::string cf_getmiddlestr (std::string srcstr, std::string startmarkstr, std::string EndMarkStr)
	size_t Startpos, Endpos, length;
	startpos = Srcstr.find (startmarkstr, 0);
	Endpos = Srcstr.find (endmarkstr, 0);
	Length = Endpos-startpos-startmarkstr.size ();
	std::string resstr = srcstr.substr (startpos + startmarkstr.size (), length);//The second parameter represents the length return

The part of the string that precedes the tag string

std::string cf_getstartstr (std::string srcstr, std::string endmarkstr)
{size_t endpos  ;
	Endpos = Srcstr.find (endmarkstr, 0);
	std::string resstr = srcstr.substr (0, endpos);
	return resstr;
The part of the string after the token string

std::string cf_getendstr (std::string srcstr, std::string startmarkstr)
{size_t startpos
	, length;
	startpos = Srcstr.find (startmarkstr, 0);
	Length = Srcstr.size ()-startpos-startmarkstr.size ();
	std::string resstr = srcstr.substr (startpos + startmarkstr.size (), length);
	return resstr;

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