使用每个（

Question

我有大量的选择下拉菜单，我正在尝试使用每个（）获取每个选定的值。我似乎无法做对。我该怎么做呢？

这是我的代码：

$('#aTable select option:selected').each(function(){
    console.log($(this).text());  
});

Answer 1

enter code here

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

public class Buttons extends Applet implements ActionListener {
    int num1 = 0;
    int num2 = 0;
    int num3 = 0;
    int num4 = 0;
    double sum = 5;
    Label total, vend, welc;
    TextArea result;

    public void init()
    {
        setLayout(new GridLayout(5, 0));

        welc = new Label ("  Welcome to the Buttons!");
        add(welc);
        vend = new Label ("Please press a button now.");
        add(vend);

        b1 = new Button("Bread");
        add(b1);
        b1.addActionListener(this);

        b2 = new Button("Butter");
        add(b2);
        b2.addActionListener(this);

        b3 = new Button("Soup");
        add(b3);
        b3.addActionListener(this);

        b4 = new Button("Water");
        add(b4);
        b4.addActionListener(this);

        b5 = new Button("Finish and pay");
        add(b5);
        b5.addActionListener(this);

        cancel = new Button("Cancel");
        add(cancel);
        cancel.addActionListener(new ActionListener(){
            @Override
                public void actionPerformed(ActionEvent e){
                Object obj=e.getSource();
                if (obj == cancel)
                {
                result.requestFocusInWindow();
                result.selectAll();
                result.setText("");
                num1 = 0; num2 = 0; num3 = 0; num4 = 0;
                }
        }
});

        total = new Label ("     You order total");
        add(total);
        result = new TextArea ( 10, 30);
        add(result);
        result.setEditable(false);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == b1){
            num1++;
            showStatus("You have chosen " + num1 + " bread");}
        if (e.getSource() == b2){
            num2++;
            showStatus("You have chosen " + num2 + " butter");}
        if (e.getSource() == b3){
            num3++;
            showStatus("You have chosen " + num3 + " soup");}
        if (e.getSource() == b4){
            num4++;
            showStatus("You have chosen " + num4 + " water");}
        if (e.getSource() == b5){
            result.requestFocusInWindow();
            sum = addition(num1, num2, num3, num4);
             result.setText(" Bread: "+ num1 +" selected\n"
            +" Butter: "+ num2 +" selected\n"
            +" Soup: "+ num3 +" selected\n"
            +" Water: "+ num4 +" selected\n"
            + "Total money due is: € " +Double.toString(sum));
            }
}

        public double addition(int x, int y, int z, int t)
            {
                return 1.2*x + 3.1*y + 2*z + 1.5*t;
    }
    Button b1, b2, b3, b4, b5, cancel;

}

Answer 2

使用#include <iostream> #include <type_traits> #include <unordered_map> #include <string> std::string Serialize(std::string s) { return '"' + s + '"'; } template < typename T, typename = typename std::enable_if<std::is_arithmetic<T>::value>::type > std::string Serialize(T n) { return std::to_string(n); } template <typename Key, typename Val, typename ...Other> std::string Serialize(typename std::unordered_map<Key, Val, Other...> const &um) { std::string result = "{"; bool comma = false; for(const auto& kv : um) { if(comma) { result += ','; } else { comma = true; } result += Serialize(kv.first); result += ':'; result += Serialize(kv.second); } result += '}'; return result; } int main() { std::unordered_map<std::string, int> mymap; mymap["one"] = 1; mymap["two"] = 2; auto serialized = Serialize(mymap); std::cout << serialized << '\n'; } 获取所选文本。它的工作原理

<强>演示： -

＆＃13;

＆＃13;

{"two":2,"one":1}

＆＃13;

this.options[this.selectedIndex].text

＆＃13;

＆＃13;

＆＃13;