我正在编写一个 C++ 控制台应用程序。在使用 size(int) rowSize 和 columnSize 创建一个矩阵后，我想将文本文件中的字母写入矩阵，但是由于读取器的位置是-1，所以 while 循环永远不会运行，而且我无法将其设为 0。有什么想法吗？
void writeText2Vec(ifstream & reader, tmatrix<char> & table){
string s;
int length, row = 0, column = 0; //beginning: column and
//row ids are set to 0.
reader.seekg(0); //reset the pointer to start
cout << reader.tellg(); // it results in -1.
while (getline(reader,s)){
//for each line while loop occurs.
length = s.length();
for(column = 0; column < length; column++)
{
table[row][column] = s.at(column);
//writing the letter to matrix.
}
row++;
}
bool openFile(ifstream & reader, string filename){
reader.open(filename.c_str());
if (reader.fail()){
exit("File cannot be found.");
return false;
}
else {
return true;
}
}
bool check(ifstream & reader, int & rowSize, int & columnSize){
//checks for valid characters, if they are
//alphabetical or not and for the length.
string s;
int len = 0, max = 0;
while (getline(reader,s)){
//runs for every line.
rowSize++; //calculation of row size
while (len < s.length()){
if (!(isalpha(s.at(len)))){
// Check to see if all characters are alphabetic.
exit("Matrix contains invalid characters!");
return false;
}
len++;
}
if (max == 0){
//if max is not set.
max = len;
len = 0;
}
else if (!(max == len)){
//if they are different, then appropriate
//error message is returned.
exit("Matrix is not in a correct format!");
return false;
}
else {
//else it resets.
len = 0;
}
}
rowSize -= 1;
columnSize = s.length(); //the last length is equal to column size
return true;
}