傳遞命令行參數

Question

好吧，我已經更新了我的代碼，但我仍然不確定如何使用我傳遞的命令行參數的向量。 我試着像我下面的代碼一樣設置它，但它不會編譯。 它給我一個錯誤，它無法找到argc和argv：

1> c：\\ users \\ chris \\ documents \\ visual studio 2008 \\ projects \\ cplusplustwo \\ cplusplustwo \\ application.h（32）：錯誤C2065：'argc'：未聲明的標識符1> c：\\ users \\ chris \\ documents \\ visual studio 2008 \\ projects \\ cplusplustwo \\ cplusplustwo \\ application.h（32）：錯誤C2065：'argv'：未聲明的標識符

main.cpp中

#include "application.h"

int main(int argc,char *argv[]){
    vector<string> args(argv, argv + argc);
    return app.run(args);    
}

application.h

#include <boost/regex.hpp>
#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include "time.h"
using namespace std;



class application{
private:
    //Variables
    boost::regex expression;
    string line;
    string pat;
    string replace;
    int lineNumber;
    char date[9];
    char time[9];


    void commandLine(vector<string> args){
        string  expression="";    // Expression
        string  textReplace="";   // Replacement Text
        string  inputFile="";     // Input File
        string  outputFile="";    // Output Directory
        int optind=1;
        // decode arguments
        for(vector<string>::iterator i = args.begin(); i != args.end(); ++i){
            while ((optind < argc) && (argv[optind][0]=='-')) {
                string sw = argv[optind];
                if (*i == "-e") {
                    optind++;
                    expression = argv[optind];
                }
                else if (*i == "-t") {
                    optind++;
                    textReplace = argv[optind];
                }
                else if (*i == "-i") {
                    optind++;
                    inputFile = argv[optind];
                }
                else if (*i == "-o") {
                    optind++;
                    outputFile = argv[optind];
                }
                else{
                    cout << "Unknown switch: " 
                        << argv[optind] << "Please enter one of the correct parameters:\n" 
                        << "-e + \"expression\"\n-t + \"replacement Text\"\n-i + \"Input File\"\n-o + \"Onput File\"\n";
                    optind++;
                }
            }
        }
    }
    //Functions
    void getExpression(){
        cout << "Expression: ";
        getline(cin,pat);
        try{
            expression = pat;
        }
        catch(boost::bad_expression){
            cout << pat << " is not a valid regular expression\n";
            exit(1);
        }
    }

    void boostMatch(){
        //Define replace {FOR TESTING PURPOSES ONLY!!! REMOVE BEFORE SUBMITTING!!
        replace = "";
        _strdate_s(date);
        _strtime_s(time);
        lineNumber = 0;
        //Files to open
        //Input Files
        ifstream in("files/trff292010.csv");
            if(!in) cerr << "no file\n";
        //Output Files
        ofstream newFile("files/NEWtrff292010.csv");
        ofstream copy("files/ORIGtrff292010.csv");
        ofstream report("files/REPORT.dat", ios.app);
        lineNumber++;
        while(getline(in,line)){
            lineNumber++;
            boost::smatch matches;
            copy << line << '\n';
            if (regex_search(line, matches, expression)){
                for (int i = 0; i<matches.size(); ++i){
                    report << "Time: " << time << "Date: " << date << '\n'
                        << "Line " << lineNumber <<": " << line << '\n';
                    newFile << boost::regex_replace(line, expression, replace) << "\n";

                }
            }else{
                newFile << line << '\n';
            }
        }
    }

public:
    void run(vector<string> args){
        commandLine(vector<string> args);
        getExpression();
        boostMatch();
    }
};

原始郵政

我想將命令行參數傳遞給main。 這是高級C ++類的功課。 我需要使用向量傳遞命令行，我不確定我是否正在做所有事情。 我會把它傳遞給像我一樣的矢量嗎？ 還有一個copy（）命令可以用來將命令行參數復制到向量而不是pushback嗎？

main.cpp

#include "application.h"

int main(int argc,char *argv[]){
    vector<string> args;
    application app;
    for (int i=1;i<argc;i++){
        args.push_back(argv[i]);
    }
    app.run(args);
    return(0);
}

application.h

#include <boost/regex.hpp>
    #include <iostream>
    #include <string>
    #include <fstream>
    #include <sstream>
    #include "time.h"
    using namespace std;

class application{
private:
    //Variables
    boost::regex expression;
    string line;
    string pat;
    string replace;
    int lineNumber;
    char date[9];
    char time[9];


    void commandLine(vector<string> args){
        string  expression="";    // Expression
        string  textReplace="";   // Replacement Text
        string  inputFile="";     // Input File
        string  outputFile="";    // Output Directory
        int optind=1;
        // decode arguments
        for(vector<string>::iterator i = args.begin(); i != args.end(); ++i){
            while ((optind < argc) && (argv[optind][0]=='-')) {
                string sw = argv[optind];
                if (*i == "-e") {
                    optind++;
                    expression = argv[optind];
                }
                else if (*i == "-t") {
                    optind++;
                    textReplace = argv[optind];
                }
                else if (*i == "-i") {
                    optind++;
                    inputFile = argv[optind];
                }
                else if (*i == "-o") {
                    optind++;
                    outputFile = argv[optind];
                }
                else{
                    cout << "Unknown switch: " 
                        << argv[optind] << "Please enter one of the correct parameters:\n" 
                        << "-e + \"expression\"\n-t + \"replacement Text\"\n-i + \"Input File\"\n-o + \"Onput File\"\n";
                    optind++;
                }
            }
        }
    }
    //Functions
    void getExpression(){
        cout << "Expression: ";
        getline(cin,pat);
        try{
            expression = pat;
        }
        catch(boost::bad_expression){
            cout << pat << " is not a valid regular expression\n";
            exit(1);
        }
    }

    void boostMatch(){
        //Define replace {FOR TESTING PURPOSES ONLY!!! REMOVE BEFORE SUBMITTING!!
        replace = "";
        _strdate_s(date);
        _strtime_s(time);
        lineNumber = 0;
        //Files to open
        //Input Files
        ifstream in("files/trff292010.csv");
            if(!in) cerr << "no file\n";
        //Output Files
        ofstream newFile("files/NEWtrff292010.csv");
        ofstream copy("files/ORIGtrff292010.csv");
        ofstream report("files/REPORT.dat", ios.app);
        lineNumber++;
        while(getline(in,line)){
            lineNumber++;
            boost::smatch matches;
            copy << line << '\n';
            if (regex_search(line, matches, expression)){
                for (int i = 0; i<matches.size(); ++i){
                    report << "Time: " << time << "Date: " << date << '\n'
                        << "Line " << lineNumber <<": " << line << '\n';
                    newFile << boost::regex_replace(line, expression, replace) << "\n";

                }
            }else{
                newFile << line << '\n';
            }
        }
    }

public:
    void run(vector<string> args){
        commandLine(vector<string> args);
        getExpression();
        boostMatch();
    }
};

Answer 1

我只想寫：

vector<string> args(argv + 1, argv + argc + !argc);

這將排除argv[0] ，但是即使argc == 0 （在Linux下可能也可能是其他操作系統），這種方式也很強大。

Answer 2

argv和argc是傳遞給main的參數。 在你的函數中你應該使用args [i]和args.length（）

Answer 3

application::commandLine()將args作為參數，但它引用argc和argv ，它們不在范圍內。 如果查看編譯器的實際錯誤消息，它應該包含一個文件名和行號，直接指向錯誤的位置。 在尋求錯誤消息的幫助時，請發布實際的錯誤消息而不是解釋它。