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React-Select

使用 React 构建的 Select 控件。 最初构建用于 KeystoneJS。

Demo & Examples

现场演示：jedwatson.github.io/react-select

Installation

使用 react-select 最简单的方法是从以下位置安装它npm 并使用 Webpack 将其构建到您的应用程序中。

yarn add react-select

然后，您可以在应用程序中导入 react-select 及其样式，如下所示：

import Select from 'react-select';
import 'react-select/dist/react-select.css';

您还可以通过包含 dist/react-select.js 和 dist/react-select 来使用独立的 UMD 构建。 css 在你的页面中。 如果这样做，您还需要包含依赖项。 例如：

<script src="https://unpkg.com/react@15.6.1/dist/react.js"></script>
<script src="https://unpkg.com/react-dom@15.6.1/dist/react-dom.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select/dist/react-select.js"></script>

<link rel="stylesheet" href="https://unpkg.com/react-select/dist/react-select.css">

Usage

React-Select 生成一个包含所选值的隐藏文本字段，因此您可以将其作为标准表单的一部分提交。 您还可以使用 onChange 事件属性监听更改。

选项应作为 Object 的 Array 提供，每个选项都具有用于呈现和搜索的 value 和 label 属性. 您可以使用 disabled 属性来指示该选项是否被禁用。

每个选项的 value 属性应该是字符串或数字。

当值更改时，onChange(selectedValueOrValues) 将触发。 请注意（从 1.0 开始）您必须处理更改并将更新后的值传递给 Select。

import React from 'react';
import Select from 'react-select';

class App extends React.Component {
  state = {
    selectedOption: '',
  }
  handleChange = (selectedOption) => {
    this.setState({ selectedOption });
    console.log(`Selected: ${selectedOption.label}`);
  }
  render() {
      const { selectedOption } = this.state;
      const value = selectedOption && selectedOption.value;

    return (
      <Select
        name="form-field-name"
        value={value}
        onChange={this.handleChange}
        options={[
          { value: 'one', label: 'One' },
          { value: 'two', label: 'Two' },
        ]}
      />
    );
  }
}

您可以自定义 valueKey 和 labelKey 道具以使用不同的选项形状。

Custom classNames

您可以为 组件提供自定义的 className 道具，该组件将被添加到基础 .Select 外部容器的 className .

内置选项渲染器还支持自定义类名，只需将 className 属性添加到 options 数组中的对象即可。

Multiselect options

您可以通过设置 multi={true} 启用多值选择。 在这种模式下：

• Selected options will be removed from the dropdown menu by default. If you want them to remain in the list, set removeSelected={false}
• The selected values are submitted in multiple <input type="hidden"> fields, use the joinValues prop to submit joined values in a single field instead
• The values of the selected items are joined using the delimiter prop to create the input value when joinValues is true
• A simple value, if provided, will be split using the delimiter prop
• The onChange event provides an array of selected options or a comma-separated string of values (eg "1,2,3") if simpleValue is true
• By default, only options in the options array can be selected. Use the Creatable Component (which wraps Select) to allow new options to be created if they do not already exist. Hitting comma (','), ENTER or TAB will add a new option. Versions 0.9.x and below provided a boolean attribute on the Select Component (allowCreate) to achieve the same functionality. It is no longer available starting with version 1.0.0.
• By default, selected options can be cleared. To disable the possibility of clearing a particular option, add clearableValue: false to that option:

var options = [
  { value: 'one', label: 'One' },
  { value: 'two', label: 'Two', clearableValue: false }
];

注意：Select 组件的 clearable 属性也应该设置为 false 以防止允许一次清除所有字段

Accessibility Note

Selected values are not focus targets, 这意味着键盘用户不能切换到它们，并且只能按顺序使用退格键删除它们。 这并不理想，我正在寻找未来的其他选择； 同时，如果您想使用实现 tabIndex 和键盘事件处理的自定义 valueComponent，请参见#2098 示例。

Async options

如果您想异步加载选项，请使用 Async 导出并提供 loadOptions 函数。

该函数有两个参数 String input, Function callback，当输入文本改变时将被调用。

当您的异步进程完成获取选项时，将它们传递给对象 { options: [] } 中的 callback(err, data)。

选择控件将智能地缓存已获取的输入字符串的选项。 缓存的结果集将在输入更具体的搜索时进行过滤，因此如果您的异步过程只会为更具体的查询返回较小的结果集，还可以在回调对象中传递 complete: true。 可以通过将 cache 设置为 false 来禁用缓存（请注意 complete: true 将无效）。

除非您指定 autoload={false} 属性，否则控件将在安装时自动加载默认选项集（即 input: ''）。

import { Async } from 'react-select';

const getOptions = (input, callback) => {
  setTimeout(() => {
    callback(null, {
      options: [
        { value: 'one', label: 'One' },
        { value: 'two', label: 'Two' }
      ],
      // CAREFUL! Only set this to true when there are no more options,
      // or more specific queries will not be sent to the server.
      complete: true
    });
  }, 500);
};

<Async
    name="form-field-name"
    loadOptions={getOptions}
/>

Note about filtering async options

Async 组件不会更改根据用户输入过滤选项的默认行为，但如果您已经在服务器端过滤选项，您可能需要自定义或禁用此功能（请参阅 < a href="#filtering-options">过滤选项如下）。 例如，如果您想完全禁用客户端过滤，您可以这样做：

filterOptions={(options, filter, currentValues) => {
  // Do no filtering, just return all options
  return options;
}}

Async options with Promises

loadOptions 支持 Promises，它的使用方式与回调非常相似。

适用于带回调的 loadOptions 的所有内容仍然适用于 Promises 方法（例如缓存、自动加载等）

。使用 fetch API 和 ES6 语法的示例，以及返回一个对象，如：

import { Async } from 'react-select';

/*
 * assuming the API returns something like this:
 *   const json = [
 *      { value: 'one', label: 'One' },
 *      { value: 'two', label: 'Two' }
 *   ]
 */

const getOptions = (input) => {
  return fetch(`/users/${input}.json`)
    .then((response) => {
      return response.json();
    }).then((json) => {
      return { options: json };
    });
}

<Async
  name="form-field-name"
  value="one"
  loadOptions={getOptions}
/>

Async options loaded externally

如果您想从 Select 组件异步加载选项，您可以通过传入 isLoading< 让 Select 组件显示加载微调器/code> 属性设置为 true。

import Select from 'react-select';

let isLoadingExternally = true;

<Select
  name="form-field-name"
  isLoading={isLoadingExternally}
  ...
/>

User-created tags

Creatable 组件使用户能够在 react-select 中创建新标签。 它装饰了一个Select，因此除了几个自定义属性（如下所示）之外，它还支持所有默认属性（例如单/多模式、过滤等）。 最简单的使用方法如下：

import { Creatable } from 'react-select';

function render (selectProps) {
  return <Creatable {...selectProps} />;
};

Combining Async and Creatable

如果您同时需要async 和creatable 功能，请使用AsyncCreatable HOC。 它将 Async 和 Creatable 组件联系在一起，并支持它们的属性（如上所列）的联合。 按如下方式使用它：

import { AsyncCreatable } from 'react-select';

function render (props) {
  // props can be a mix of Async, Creatable, and Select properties
  return (
    <AsyncCreatable {...props} />
  );
}

Filtering options

您可以使用以下属性控制选项的过滤方式：

• matchPos: "start" or "any": whether to match the text entered at the start or any position in the option value
• matchProp: "label", "value" or "any": whether to match the value, label or both values of each option when filtering
• ignoreCase: Boolean: whether to ignore case or match the text exactly when filtering
• ignoreAccents: Boolean: whether to ignore accents on characters like ø or å

matchProp 和 matchPos 均默认为 "any"。 ignoreCase 默认为 true。 ignoreAccents 默认为 true。

Advanced filters

您还可以完全替换用于过滤单个选项或整个选项数组（允许自定义排序机制等）的方法

• filterOption: function(Object option, String filter) returns Boolean. Will override matchPos, matchProp, ignoreCase and ignoreAccents options.
• filterOptions: function(Array options, String filter, Array currentValues) returns Array filteredOptions. Will override filterOption, matchPos, matchProp, ignoreCase and ignoreAccents options.

。对于多选输入，在提供自定义 filterOptions 方法时，请记住从返回的选项数组中排除当前值。

Filtering large lists

每次过滤器文本更改时，默认的 filterOptions 方法都会扫描选项数组以查找匹配项。 这很好用，但随着选项数组增长到数百个对象，速度可能会变慢。 对于更大的选项列表，自定义过滤器函数如 react-select-fast-filter-options 会产生更好的结果。

Efficiently rendering large lists with windowing

menuRenderer 属性可用于覆盖默认的选项下拉列表。 这应该在列表很大（成百上千个项目）时完成，以便更快地呈现。 然后可以使用像 react-virtualized 这样的窗口库来更有效地呈现下拉菜单像这样。 最简单的方法是使用 react-virtualized-select HOC。 该组件装饰了一个 Select 并使用反应虚拟化的 VirtualScroll 组件来呈现选项。 此组件的演示和文档可在此处获得。

您还可以指定自己的自定义渲染器。 自定义 menuRenderer 属性接受以下命名参数：

Parameter	Type	Description
focusedOption	Object	The currently focused option; should be visible in the menu by default.
focusOption	Function	Callback to focus a new option; receives the option as a parameter.
labelKey	String	Option labels are accessible with this string key.
optionClassName	String	The className that gets used for options
optionComponent	ReactClass	The react component that gets used for rendering an option
optionRenderer	Function	The function that gets used to render the content of an option
options	Array<Object>	Ordered array of options to render.
selectValue	Function	Callback to select a new option; receives the option as a parameter.
valueArray	Array<Object>	Array of currently selected options.

Updating input values with onInputChange

您可以通过提供返回新值的 onInputChange 回调来操纵输入。 请注意：当您只想使用onInputChange 来监听输入更新时，您仍然必须返回未更改的值！

function cleanInput(inputValue) {
    // Strip all non-number characters from the input
    return inputValue.replace(/[^0-9]/g, "");
}   

<Select
    name="form-field-name"
    onInputChange={cleanInput}
/>

Overriding default key-down behaviour with onInputKeyDown

Select 监听 keyDown 事件来选择项目，通过箭头键导航下拉列表等。 您可以通过提供 onInputKeyDown 回调来扩展或覆盖此行为。

function onInputKeyDown(event) {
    switch (event.keyCode) {
        case 9:   // TAB
            // Extend default TAB behaviour by doing something here
            break;
        case 13: // ENTER
            // Override default ENTER behaviour by doing stuff here and then preventing default
            event.preventDefault();
            break;
    }
}

<Select
    {...otherProps}
    onInputKeyDown={onInputKeyDown}
/>

Select Props

Property	Type	Default	Description
aria-describedby	string	undefined	HTML ID(s) of element(s) that should be used to describe this input (for assistive tech)
aria-label	string	undefined	Aria label (for assistive tech)
aria-labelledby	string	undefined	HTML ID of an element that should be used as the label (for assistive tech)
arrowRenderer	function	undefined	Renders a custom drop-down arrow to be shown in the right-hand side of the select: arrowRenderer({ onMouseDown, isOpen }). Won't render when set to null
autoBlur	boolean	false	Blurs the input element after a selection has been made. Handy for lowering the keyboard on mobile devices
autofocus	boolean	undefined	deprecated; use the autoFocus prop instead
autoFocus	boolean	undefined	autofocus the component on mount
autoload	boolean	true	whether to auto-load the default async options set
autosize	boolean	true	If enabled, the input will expand as the length of its value increases
backspaceRemoves	boolean	true	whether pressing backspace removes the last item when there is no input value
backspaceToRemoveMessage	string	'Press backspace to remove {last label}'	prompt shown in input when at least one option in a multiselect is shown, set to '' to clear
className	string	undefined	className for the outer element
clearable	boolean	true	should it be possible to reset value
clearAllText	string	'Clear all'	title for the "clear" control when multi is true
clearRenderer	function	undefined	Renders a custom clear to be shown in the right-hand side of the select when clearable true: clearRenderer()
clearValueText	string	'Clear value'	title for the "clear" control
closeOnSelect	boolean	true	whether to close the menu when a value is selected
deleteRemoves	boolean	true	whether pressing delete key removes the last item when there is no input value
delimiter	string	','	delimiter to use to join multiple values
disabled	boolean	false	whether the Select is disabled or not
escapeClearsValue	boolean	true	whether escape clears the value when the menu is closed
filterOption	function	undefined	method to filter a single option (option, filterString) => boolean
filterOptions	boolean or function	undefined	boolean to enable default filtering or function to filter the options array ([options], filterString, [values]) => [options]
id	string	undefined	html id to set on the input element for accessibility or tests
ignoreAccents	boolean	true	whether to strip accents when filtering
ignoreCase	boolean	true	whether to perform case-insensitive filtering
inputProps	object	undefined	custom attributes for the Input (in the Select-control) e.g: {'data-foo': 'bar'}
inputRenderer	function	undefined	renders a custom input component
instanceId	string	increment	instance ID used internally to set html ids on elements for accessibility, specify for universal rendering
isLoading	boolean	false	whether the Select is loading externally or not (such as options being loaded)
joinValues	boolean	false	join multiple values into a single hidden input using the delimiter
labelKey	string	'label'	the option property to use for the label
matchPos	string	'any'	(any, start) match the start or entire string when filtering
matchProp	string	'any'	(any, label, value) which option property to filter on
menuBuffer	number	0	buffer of px between the base of the dropdown and the viewport to shift if menu doesnt fit in viewport
menuContainerStyle	object	undefined	optional style to apply to the menu container
menuRenderer	function	undefined	Renders a custom menu with options; accepts the following named parameters: menuRenderer({ focusedOption, focusOption, options, selectValue, valueArray })
menuStyle	object	undefined	optional style to apply to the menu
multi	boolean	undefined	multi-value input
name	string	undefined	field name, for hidden <input /> tag
noResultsText	string	'No results found'	placeholder displayed when there are no matching search results or a falsy value to hide it (can also be a react component)
onBlur	function	undefined	onBlur handler: function(event) {}
onBlurResetsInput	boolean	true	Whether to clear input on blur or not. If set to false, it only works if onCloseResetsInput is false as well.
onChange	function	undefined	onChange handler: function(newOption) {}
onClose	function	undefined	handler for when the menu closes: function () {}
onCloseResetsInput	boolean	true	whether to clear input when closing the menu through the arrow
onFocus	function	undefined	onFocus handler: function(event) {}
onInputChange	function	undefined	onInputChange handler/interceptor: function(inputValue: string): string
onInputKeyDown	function	undefined	input keyDown handler; call event.preventDefault() to override default Select behaviour: function(event) {}
onMenuScrollToBottom	function	undefined	called when the menu is scrolled to the bottom
onOpen	function	undefined	handler for when the menu opens: function () {}
onSelectResetsInput	boolean	true	whether the input value should be reset when options are selected. Also input value will be set to empty if 'onSelectResetsInput=true' and Select will get new value that not equal previous value.
onValueClick	function	undefined	onClick handler for value labels: function (value, event) {}
openOnClick	boolean	true	open the options menu when the control is clicked (requires searchable = true)
openOnFocus	boolean	false	open the options menu when the control gets focus
optionClassName: string	undefined	additional class(es) to apply to theelements
optionComponent	function	undefined	option component to render in dropdown
optionRenderer	function	undefined	custom function to render the options in the menu
options	array	undefined	array of options
removeSelected	boolean	true	whether the selected option is removed from the dropdown on multi selects
pageSize	number	5	number of options to jump when using page up/down keys
placeholder	string or node	'Select …'	field placeholder, displayed when there's no value
required	boolean	false	applies HTML5 required attribute when needed
resetValue	any	null	value to set when the control is cleared
rtl	boolean	false	use react-select in right-to-left direction
scrollMenuIntoView	boolean	true	whether the viewport will shift to display the entire menu when engaged
searchable	boolean	true	whether to enable searching feature or not
searchPromptText	string or node	'Type to search'	label to prompt for search input
simpleValue	boolean	false	pass the value to onChange as a string
style	object	undefined	optional styles to apply to the control
tabIndex	string or number	undefined	tabIndex of the control
tabSelectsValue	boolean	true	whether to select the currently focused value when the [tab] key is pressed
trimFilter	boolean	false	whether to trim whitespace from the filter value
value	any	undefined	initial field value
valueComponent	function		function which returns a custom way to render/manage the value selected <CustomValue />
valueKey	string	'value'	the option property to use for the value
valueRenderer	function	undefined	function which returns a custom way to render the value selected function (option) {}
wrapperStyle	object	undefined	optional styles to apply to the component wrapper

Async Props

Property	Type	Default	Description
autoload	boolean	true	automatically call the loadOptions prop on-mount
cache	object	undefined	Sets the cache object used for options. Set to false if you would like to disable caching.
loadingPlaceholder	string or node	'Loading…'	label to prompt for loading search result
loadOptions	function	undefined	function that returns a promise or calls a callback with the options: function(input, [callback])

Creatable properties

Property	Type	Description
children	function	Child function responsible for creating the inner Select component. This component can be used to compose HOCs (eg Creatable and Async). Expected signature: (props: Object): PropTypes.element
isOptionUnique	function	Searches for any matching option within the set of options. This function prevents duplicate options from being created. By default this is a basic, case-sensitive comparison of label and value. Expected signature: ({ option: Object, options: Array, labelKey: string, valueKey: string }): boolean
isValidNewOption	function	Determines if the current input text represents a valid option. By default any non-empty string will be considered valid. Expected signature: ({ label: string }): boolean
newOptionCreator	function	Factory to create new option. Expected signature: ({ label: string, labelKey: string, valueKey: string }): Object
onNewOptionClick	function	new option click handler, it calls when new option has been selected. function(option) {}
shouldKeyDownEventCreateNewOption	function	Decides if a keyDown event (eg its keyCode) should result in the creation of a new option. ENTER, TAB and comma keys create new options by default. Expected signature: ({ keyCode: number }): boolean
promptTextCreator	function	Factory for overriding default option creator prompt label. By default it will read 'Create option "{label}"'. Expected signature: (label: String): String

Methods

使用 focus() 方法为控件提供焦点。 元素上的所有其他方法都应视为私有方法。

// focuses the input element
<instance>.focus();

Contributing

有关如何贡献的信息，请参阅我们的 CONTRIBUTING.md。

感谢以下项目的启发：Selectize（在行为和用户体验方面），React-Autocomplete（作为高质量的 React Combobox 实现），以及其他选择控件，包括 选择 和选择2。

License

麻省理工学院许可。 版权所有 (c) Jed Watson 2018。