當計算C++中的文本文件中的文本行數時出現錯誤

Question

我正在嘗試計算文本文件中的行數，但每次運行此代碼時，我都將1987121509作爲行數。你能告訴我如何修改我的代碼以獲得正確的行數？謝謝。

下面的代碼：

#include <iostream> 
#include <string> 
#include <fstream> 
using namespace std; 

int main() 
{ 
string line; 
int numLine; 

ifstream dataFile; 
dataFile.open("fileforstring.txt"); 

if(!dataFile) 
{ 
    cout<<"Error opening file."; 
} 

else 
{ 
    cout<<"File opened successfully"; 
} 

while(getline(dataFile,line)) 
{ 
    ++numLine; //increment numLine each time a line is found 
} 

cout<<"\nNo of lines in text file is "<<numLine; 

dataFile.close(); 

return 0; 
} 

Answer 1

下面是正確的代碼不正確初始化變量的 愚蠢的錯誤（我問這個問題後發現）。

#include <iostream> 
#include <string> 
#include <fstream> 
using namespace std; 
int main() 
{ 
string line; 
int numLine = 0; //didn't set it to zero. 
ifstream dataFile; 
dataFile.open("fileforstring.txt"); 

if(!dataFile) 
{ 
    cout<<"Error opening file."; 
} 

else 
{ 
    cout<<"File opened successfully"; 
} 

while(getline(dataFile,line)) 
{ 
    ++numLine; 
} 

cout<<"\nNo of lines in text file is "<<numLine; 

dataFile.close(); 

return 0; 
}