JavaJButton只需要工作一次

我不明白，我怎么能做到这一点，若点击按钮，它只会检查一次Playerlevel和升级。直到没有足够的钱

1.试试看

if（ae.getActionCommand（）.equals（“升级LVL”）{
如果（car.Playerlevel==1）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（空，“您已获得1个玩家级别”，“祝贺”，JOptionPane.INFORMATION_消息）；
}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要100美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}           
如果（car.Playerlevel==2）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得2个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要200美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==3）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得3个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要300美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==4）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得4个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要400美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==5）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得5个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要500美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==6）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得6个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要600美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==7）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得7个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要700美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==8）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得8个玩家级别”，“祝贺”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要800美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==9）{
如果（car.money>=2）{
汽车.货币-=2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您已获得9个玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
如果（车钱<2）{
JOptionPane.showMessageDialog（null，“您没有足够的钱。此升级需要900美元”，“没有钱”，JOptionPane.ERROR_MESSAGE）；}
}
如果（car.Playerlevel==10）{
JOptionPane.showMessageDialog（null，“您已获得最高玩家级别”，“恭喜”，JOptionPane.INFORMATION_MESSAGE）；}
}

2.试试看

if（ae.getActionCommand（）.equals（“升级LVL”）{
对于（int i=0；i=i*2）{
car.money-=i*2；
car.Playerlevel+=1；
JOptionPane.showMessageDialog（null，“您购买了”+i+“玩家级别”。，“Congrelations”，JOptionPane.INFORMATION_MESSAGE）；}
否则{
JOptionPane.showMessage
 if(ae.getActionCommand().equals("Upgrade LVL")) {  
                if (car.Playerlevel == 1){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 1 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);
                        }
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 100", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }           
                if (car.Playerlevel == 2){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 2 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 200", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 3){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 3 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 300", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 4){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 4 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 400", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 5){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 5 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 500", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 6){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 6 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 600", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 7){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 7 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 700", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 8){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 8 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 800", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 9){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 9 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 900", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 10){
                        JOptionPane.showMessageDialog (null, "You have gained MAX Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}                            
            }

if(ae.getActionCommand().equals("Upgrade LVL")) {           
            for (int i =0; i <11; i++){                 
                   if (car.Playerlevel == i){
                    if (car.money >= i*2){
                        car.money -= i*2;
                        car.Playerlevel +=1;                   
                        JOptionPane.showMessageDialog (null, "You have purchased " + i + " Player level.", "Congralations", JOptionPane.INFORMATION_MESSAGE);}                          
                    else{                           
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 100*lvl", "No Money", JOptionPane.ERROR_MESSAGE);}               
                   }
            }
        }

 for (int i =0; i <11; i++)

 for (int i=10; i>= 0; i--)