删除包含一个字

Question

我试图删除包含从文本文件 特定字线一条线，但它不工作

void deleteline() 
{ 
    string line, deletecontact; 
    cout << "Plase enter the contact (name or number) to delete:"; 
    cin >> deletecontact; 
    ifstream file; 
    ofstream outfile; 
    file.open("data.txt"); 
    outfile.open("newM.txt"); 
    while (getline(file, line)) { 
     if (line != deletecontact) { 
      outfile << line << endl; 
     } 
    } 
    outfile.close(); 
    file.close(); 
    remove("movieList.txt"); 
    rename("newM.txt", "data.txt"); 
} 

预先感谢您

Answer 1

您只有在删除线他们是平等的（即line != deleteContact）。如果你想删除，正如你所说，只包含这个字线，你应该写类似以下内容：

if (strstr(line.c_str(), deleteContact.c_str()) == nullptr) ...