如何使用react js JSX在下拉列表中創建年份列表

Question

我想在 react JSX 中創建一個年份列表

我有 Jquery 的代碼，請看下面。

var minOffset = 0, maxOffset = 60; // Change to whatever you want
var thisYear = (new Date()).getFullYear();
var select = $('<select>');

for (var i = minOffset; i <= maxOffset; i++) {
    var year = thisYear - i;
    $('<option>', {value: year, text: year}).appendTo(select);
}

select.appendTo('body');

http://jsfiddle.net/DhpBg/739/

Answer 1

首先，在數組中生成所有需要的年份

const year = (new Date()).getFullYear();
const years = Array.from(new Array(20),( val, index) => index + year);

獲得年份后，您可以遍歷數組並將其列在select控件中。

考慮以下代碼片段

constructor(props){
  super(props);
  const year = (new Date()).getFullYear();
  this.years = Array.from(new Array(20),(val, index) => index + year);
}

render() {
  return(
    ...
    <select>
     {
       this.years.map((year, index) => {
         return <option key={`year${index}`} value={year}>{year}</option>
       })
     }
    </select>
    ...
  );
}

希望這會有所幫助！

Answer 2

這可能會有所幫助。 確保您正確設置了正確的狀態並在 onHandleChange 中處理您的更新。

 const minOffset = 0; const maxOffset = 60; class DatePicker extends React.Component { constructor() { super(); const thisYear = (new Date()).getFullYear(); this.state = { thisYear: thisYear, selectedYear: thisYear } } onHandleChange = (evt) => { // Handle Change Here // alert(evt.target.value); this.setState({ selectedYear: evt.target.value }); }; render() { const { thisYear, selectedYear } = this.state; const options = []; for (let i = minOffset; i <= maxOffset; i++) { const year = thisYear - i; options.push(<option value={year}>{year}</option>); } return ( <div> <select value={this.selectedYear} onChange={this.onHandleChange}> {options} </select> </div> ); } } /* * Render the above component into the div#app */ ReactDOM.render(<DatePicker />, document.getElementById('app'));

 <script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script> <div id="app"></app>

Answer 3

class DropDown extends Component {

render() {
    let minOffset = 0, maxOffset = 10;
    let thisYear = (new Date()).getFullYear();
    let allYears = [];
    for(let x = 0; x <= maxOffset; x++) {
        allYears.push(thisYear - x)
    }

    const yearList = allYears.map((x) => {return(<option key={x}>{x}</option>)});
    return(
        <div>
            <select>
                {yearList}
            </select>
        </div>
    );
}

}

無論如何，這可能不是最佳解決方案，但這只是為了讓您了解如何去做。

Answer 4

另一種方式：

  getDropList = () => {
    const year = new Date().getFullYear();
    return (
      Array.from( new Array(50), (v,i) =>
        <option key={i} value={year+i}>{year+i}</option>
      )
    );
  };

小提琴： https : //jsfiddle.net/knik/n5u2wwjg/9637/