Question

我真的很执着于Java的工作。只是一个初学者，我需要编写一个捐赠管理系统，该系统需要读取2个文件（捐赠者记录和说明），我需要阅读它们并验证捐赠者记录，然后print写入经过验证的记录并以某些toString格式打印。 / p>

需要读取以下记录：（字段可以按任何顺序排列

interface IState{
    users : Account[];
    user: Account;
    editingIndex: number | null;
}

// In constructor
constructor(props:any){
   super(props);
   this.state= { 
                     users: [],
                     user: {
                               name: '',
                               email: '',
                               phone: '',
                           },
                     editingIndex: null
               }
}
showDetails = (i:number) => { 
    this.setState ({user: this.state.users[i], editingIndex: i});
    console.log(i);
}

handleChange = ( event: React.ChangeEvent<HTMLInputElement>) => {
    let user = {...this.state.user,
        [event.currentTarget.name]:event.currentTarget.value};
    this.setState({user});
    // If we currently editing existing item, update it in array
    if (this.state.editingIndex !== null) {
        let users = [...this.state.users];
        users[this.state.editingIndex] = user;
        this.setState({users});
    }
}
removeAccount = (i:number) => {
   let users = [...this.state.users];
   // If we're going to delete existing item which we've been editing, set editingIndex to null, to specify that editing ends
   if (this.state.editingIndex === i)
       this.setState({user: {name: '', email: '', phone: ''}, editingIndex: null});
   users.splice(i,1);
   this.setState({users},()=>{console.log('setting the data')});
 }

 onAdd = () => {
    e.preventDefault();
    // If we NOT editing, but adding new editingIndex will be null so add user to users array. If we editing existing element it's no need to add it once again.
    if (this.state.editingIndex === null)
        this.setState({ users: [...this.state.users, this.state.user] });
    this.setState ({ editingIndex: null, 
                user: { name:'', email: '', phone: ''}
              },()=>{console.log('adding')});
 }
 // render will have no change

我已经创建了3个扫描仪， 1.扫描记录文件 2.扫描每一行 3.扫描关键字和值

但是随后我得到了结果文件，其中每个字段都创建了一个捐赠者对象，而不是将所有字段都放在一个对象中。

输出如下：

phone 02111111
name Posephine Bloggs
birthday 01-06-1980
address 1 Grace Street, Lane Cove, NSW
postcode 2066
recipient dog care, the disabled
donation 100, 300

address 102 Smith St, Summer hill, NSW
postcode 2130
name Posephine Esmerelda Bloggs
birthday 13-05-1960
phone 11222009
recipient animal protection, lifecare
donation 50, 200

Answer 1

您的错误在这里：

while(scanRecord.hasNextLine()) {
    donator a = new donator();

    String line = scanRecord.nextLine();

这意味着您将为阅读的每一行创建一个新的捐赠者，而您应该在阅读空白一行时创建一个新的捐赠者。

解决此问题的一种方法是将a的声明移出while循环，并且仅在读取的行为空白时才初始化a。您还应该将捐赠者添加到else分支的列表中。

donator a = new donator();
while(scanRecord.hasNextLine()) {
    String line = scanRecord.nextLine();
    if (!line.isBlank()) {
        ...
    } else {
        donatorList.addDonator(a);
        a = new donator();
    }

初学者作业需要帮助！扫描文件->数据验证-> Printwriter

1 个答案: