如何从文本字段获取Long值并将表单发送到ArrayList

How would I get a long data type in Java? For example, I would get a string like this:

我如何在Java中获得长数据类型?例如,我会得到一个这样的字符串:

String thisString = thisString.getText();

But I try the same with a long data type and it doesn't work. I need it to send it to an ArrayList, and this is the whole code:

但我尝试使用长数据类型,但它不起作用。我需要它将它发送到ArrayList,这是整个代码:

package dao;

import entities.*;
import java.util.*;
import javax.swing.JTextField;
import java.text.*;
import javaapplication1.*;

public class ProductModel{

    public List<Product> findAll(){
        try {
            List<Product> forms = new ArrayList<Product>();
            JTextField textDate;
            JTextField textFecha;
            JTextField textTotal;
            return forms;
        } catch (Exception e){
            return null;
        }
   }
}

That's my array, and then I have this other file here:

这是我的数组,然后我在这里有另一个文件:

public class Product{

   public String date;
   public String fac;
   public Long total;
}

And then finally, the button that sends the data that to the ArrayList:

最后,将数据发送到ArrayList的按钮:

    @Override
    public void actionPerformed(ActionEvent e) {

        Product form = new Product();
        form.date = textDate.getText();
        form.fac = textFac.getText();
        form.total = textTotal.getText();
        forms.add(form);
    }
});

But it doesn't seem to work.

但它似乎没有用。

1 个解决方案

#1

A String is not a Long. That is the reason compiler is shouting on you. You need to parse it.

字符串不长。这就是编译器对你大喊大叫的原因。你需要解析它。

form.total = Long.parseLong(textTotal.getText());

Make sure you have a null check and assign it to 0 if the string is null.

确保您具有空检查,并在字符串为空时将其指定为0。

And once you fix the issue, please give a read to Encapsulation.

一旦你解决了这个问题,请阅读Encapsulation。

#1