Question

我在代码中遇到了一些错误，因为我是C ++的新手，我正在努力弄清楚我做错了什么以及解决方案是什么。我用Google搜索了一下，但我发现没有什么是有道理的，所以如果有人能给我一些帮助，那就太棒了，这样我就可以从中学习。

错误全都在第23行，即搜索（令牌）;

Error   C2672   'search': no matching overloaded function found TakeTwo d:\desktop\twittersearch\taketwo\taketwo\taketwo.cpp    23  
Error   C2780   '_FwdIt1 std::search(_FwdIt1,_FwdIt1,_FwdIt2,_FwdIt2)': expects 4 arguments - 1 provided    TakeTwo d:\desktop\twittersearch\taketwo\taketwo\taketwo.cpp    23  
Error   C2780   '_FwdIt1 std::search(_FwdIt1,_FwdIt1,_FwdIt2,_FwdIt2,_Pr)': expects 5 arguments - 1 provided    TakeTwo d:\desktop\twittersearch\taketwo\taketwo\taketwo.cpp    23

代码：

#include "stdafx.h"
#include <cstring>
#include <fstream>
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

string token;

int main()
{
    int menu_choice;
    cout << "Main Menu:\n";
    cout << "1. Search for \"winner\" \n";

    cout << "Please choose an option: ";
    cin >> menu_choice;

    if (menu_choice == '1') {
        token == "winner";
        search(token);
    } else {
        cout << "\nPlease enter a valid option\n";
        system("Pause");
        system("cls");
        main();
    }

    return 0;
}

void search(string &token)
{
    ifstream fin;
    fin.open("sampleTweets.csv");

    if (fin.is_open())
    {
        cout << "File opened successfully" << "\n";
    }
    else {
        cout << "Error opening file" << "\n";
    }

    string line;
    while (getline(fin, line)) {
        if (line.find(token) != string::npos) {
            int n = line.find(",");
            char c;
            line[n] = ' '; //Changes the comma spacing
            line.erase(remove_if(line.begin(), line.end(), [](char chr) { return chr == '\"' || chr == '\'' || chr == ','; }), //Removes the characters " ' and , from the strings
                line.end());
            line.erase(n + 1, 1); //Removes the 'b' from the beginning of each tweet
            cout << line << endl;
        }

    }

    fin.close();
    char anykey;
    cout << "press any key";
    cin >> anykey;

    return;
}

Answer 1

using namespace std;的危险。由于您在使用之前从未声明或定义search函数，因此编译器假设您的意思是std::search，它是<algorithm>标头的一部分。在使用之前确保declare您的功能将在这种情况下解决错误。

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

string token;

// Forward declare search before first use
void search(string &token);

int main()
{
    int menu_choice;
    cout << "Main Menu:\n";
    cout << "1. Search for \"winner\" \n";

    cout << "Please choose an option: ";
    cin >> menu_choice;

    if (menu_choice == '1') {
        token == "winner";
        search(token);
    }
    else {
        cout << "\nPlease enter a valid option\n";
        system("Pause");
        system("cls");
        main();
    }

    return 0;
}

Visual Studio错误：C2672＆amp; C2780

1 个答案: