从字符串中获取一个数字

Question

我有这个转换器，用于从组合框中获取或设置标签：

public class GroupConverter extends StringConverter<ListGroupsObj>
{

    @Override
    public String toString(ListGroupsObj obj)
    {
        return obj.getGroupId() + " - " + obj.getGroupName();
    }

    @Override
    public ListGroupsObj fromString(String obj)
    {

        Scanner fi = new Scanner(obj);
        //anything other than alphanumberic characters, 
        //comma, dot or negative sign is skipped
        fi.useDelimiter("[^\\p{Alnum},\\.-]");
        while (true)
        {
            if (fi.hasNextInt()){
                //System.out.println("Int: " + fi.nextInt());
                return ListGroupsObj.newInstance().groupId(fi.nextInt());
            }
            break;                    
        }

        //TODO when you type for example "45 - NextGroup" you want to take only tyhe number"
        return ListGroupsObj.newInstance().groupId(fi.nextInt());
    }

}

例如，当我输入“45 - NextGroup”时，我只想从值中获取数字。你能帮我实现吗？

Answer 1

试试这个

String s="45 - Next";// the string from the box
int num=Integer.parseInt(s.split("-")[0].trim());

Answer 2

        String s="45 - Next";
        String reg = "[0-9]+";
        Pattern pattern = Pattern.compile(reg);
        Matcher matcher = pattern.matcher(s);
        while(matcher.find()) {
            String numString = matcher.group();
            int num = Integer.parseInt(numString);
            System.out.println(num);
        }