如何从 C++ 中的文本文件中获取特定字符串

Question

Lets say I have a text file with this input:

Caroline went to the sea, and she forgot her boat.

Patrick went to the sea, and he drowned.

How do I get the word sea and the whole line with the word sea?

So basically when I type sea the output needs to be:

Caroline went to the sea, and she forgot her boat.

Patrick went to the sea, and he drowned.

This is what I currently have:

int main () {

  // Create a text string, which is used to output the text file
  string myText;

  // Read from the text file
  ifstream MyReadFile("myfile.txt");

  while (getline (MyReadFile, myText)) {
  // Output the text from the file
    cout << myText;
  }

  // Close the file
  MyReadFile.close();
}

Answer 1

Well, what you just need is to iterate the lines of your file and see if the line contains the word you want. If it does, just print the line. Here is the core of what you need:

while (getline (MyReadFile, myText)) {
  if(myText.find(yourString)!=std::string::npos){
           cout<<myText<<\n;
  }
}

The if statement checks if it the string yourString (which is "sea" in your example) is a substring of line. If it is, it will output the line.