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select实现多选下拉框功能(excel下拉框实现复选)
2022-02-23 16:56  浏览:2

各位朋友大家早上好!

今天给大家带来的是 八种select下拉选择特效源码!

在日常工作中会经常遇到!

大家可以按照自己的意愿,做成喜欢的样子!

有想要文件版源码的可以私聊小编!

废话不多说,上源码!

JS:

;( function( window ) {

‘use strict’;

function hasParent( e, p ) {

if (!e) return false;

var el = e.target||e.srcElement||e||false;

while (el && el != p) {

el = el.parentNode||false;

}

return (el!==false);

};

function extend( a, b ) {

for( var key in b ) {

if( b.hasOwnProperty( key ) ) {

a[key] = b[key];

}

}

return a;

}

function SelectFx( el, options ) {

this.el = el;

this.options = extend( {}, this.options );

extend( this.options, options );

this._init();

}

SelectFx.prototype.options = {

// if true all the links will open in a new tab.

// if we want to be redirected when we click an option, we need to define a data-link attr on the option of the native select element

newTab : true,

// when opening the select element, the default placeholder (if any) is shown

stickyPlaceholder : true,

// callback when changing the value

onChange : function( val ) { return false; }

}

SelectFx.prototype._init = function() {

// check if we are using a placeholder for the native select box

// we assume the placeholder is disabled and selected by default

var selectedOpt = this.el.querySelector( ‘option[selected]’ );

this.hasDefaultPlaceholder = selectedOpt && selectedOpt.disabled;

// get selected option (either the first option with attr selected or just the first option)

this.selectedOpt = selectedOpt || this.el.querySelector( ‘option’ );

// create structure

this._createSelectEl();

// all options

this.selOpts = [].slice.call( this.selEl.querySelectorAll( ‘li[data-option]’ ) );

// total options

this.selOptsCount = this.selOpts.length;

// current index

this.current = this.selOpts.indexOf( this.selEl.querySelector( ‘li.cs-selected’ ) ) || -1;

// placeholder elem

this.selPlaceholder = this.selEl.querySelector( ‘span.cs-placeholder’ );

// init events

this._initEvents();

}

SelectFx.prototype._createSelectEl = function() {

var self = this, options = ”, createOptionHTML = function(el) {

var optclass = ”, classes = ”, link = ”;

if( el.selectedOpt && !this.foundSelected && !this.hasDefaultPlaceholder ) {

classes += ‘cs-selected ‘;

this.foundSelected = true;

}

// extra classes

if( el.getAttribute( ‘data-class’ ) ) {

classes += el.getAttribute( ‘data-class’ );

}

// link options

if( el.getAttribute( ‘data-link’ ) ) {

link = ‘data-link=’ + el.getAttribute( ‘data-link’ );

}

if( classes !== ” ) {

optclass = ‘class=”‘ + classes + ‘” ‘;

}

return ‘<li ‘ + optclass + link + ‘ data-option data-value=”‘ + el.value + ‘”><span>’ + el.textContent + ‘</span></li>’;

};

[].slice.call( this.el.children ).forEach( function(el) {

if( el.disabled ) { return; }

var tag = el.tagName.toLowerCase();

if( tag === ‘option’ ) {

options += createOptionHTML(el);

}

else if( tag === ‘optgroup’ ) {

options += ‘<li class=”cs-optgroup”><span>’ + el.label + ‘</span><ul>’;

[].slice.call( el.children ).forEach( function(opt) {

options += createOptionHTML(opt);

} )

options += ‘</ul></li>’;

}

} );

var opts_el = ‘<div class=”cs-options”><ul>’ + options + ‘</ul></div>’;

this.selEl = document.createElement( ‘div’ );

this.selEl.className = this.el.className;

this.selEl.tabIndex = this.el.tabIndex;

this.selEl.innerHTML = ‘<span class=”cs-placeholder”>’ + this.selectedOpt.textContent + ‘</span>’ + opts_el;

this.el.parentNode.appendChild( this.selEl );

this.selEl.appendChild( this.el );

}

SelectFx.prototype._initEvents = function() {

var self = this;

// open/close select

this.selPlaceholder.addEventListener( ‘click’, function() {

self._toggleSelect();

} );

// clicking the options

this.selOpts.forEach( function(opt, idx) {

opt.addEventListener( ‘click’, function() {

self.current = idx;

self._changeOption();

// close select elem

self._toggleSelect();

} );

} );

// close the select element if the target it´s not the select element or one of its descendants..

document.addEventListener( ‘click’, function(ev) {

var target = ev.target;

if( self._isOpen() && target !== self.selEl && !hasParent( target, self.selEl ) ) {

self._toggleSelect();

}

} );

// keyboard navigation events

this.selEl.addEventListener( ‘keydown’, function( ev ) {

var keyCode = ev.keyCode || ev.which;

switch (keyCode) {

// up key

case 38:

ev.preventDefault();

self._navigateOpts(‘prev’);

break;

// down key

case 40:

ev.preventDefault();

self._navigateOpts(‘next’);

break;

// space key

case 32:

ev.preventDefault();

if( self._isOpen() && typeof self.preSelCurrent != ‘undefined’ && self.preSelCurrent !== -1 ) {

self._changeOption();

}

self._toggleSelect();

break;

// enter key

case 13:

ev.preventDefault();

if( self._isOpen() && typeof self.preSelCurrent != ‘undefined’ && self.preSelCurrent !== -1 ) {

self._changeOption();

self._toggleSelect();

}

break;

// esc key

case 27:

ev.preventDefault();

if( self._isOpen() ) {

self._toggleSelect();

}

break;

}

} );

}

SelectFx.prototype._navigateOpts = function(dir) {

if( !this._isOpen() ) {

this._toggleSelect();

}

var tmpcurrent = typeof this.preSelCurrent != ‘undefined’ && this.preSelCurrent !== -1 ? this.preSelCurrent : this.current;

if( dir === ‘prev’ && tmpcurrent > 0 || dir === ‘next’ && tmpcurrent < this.selOptsCount – 1 ) {

// save pre selected current – if we click on option, or press enter, or press space this is going to be the index of the current option

this.preSelCurrent = dir === ‘next’ ? tmpcurrent + 1 : tmpcurrent – 1;

// remove focus class if any..

this._removeFocus();

// add class focus – track which option we are navigating

classie.add( this.selOpts[this.preSelCurrent], ‘cs-focus’ );

}

}

SelectFx.prototype._toggleSelect = function() {

// remove focus class if any..

this._removeFocus();

if( this._isOpen() ) {

if( this.current !== -1 ) {

// update placeholder text

this.selPlaceholder.textContent = this.selOpts[ this.current ].textContent;

}

classie.remove( this.selEl, ‘cs-active’ );

}

else {

if( this.hasDefaultPlaceholder && this.options.stickyPlaceholder ) {

// everytime we open we wanna see the default placeholder text

this.selPlaceholder.textContent = this.selectedOpt.textContent;

}

classie.add( this.selEl, ‘cs-active’ );

}

}

SelectFx.prototype._changeOption = function() {

// if pre selected current (if we navigate with the keyboard)…

if( typeof this.preSelCurrent != ‘undefined’ && this.preSelCurrent !== -1 ) {

this.current = this.preSelCurrent;

this.preSelCurrent = -1;

}

// current option

var opt = this.selOpts[ this.current ];

// update current selected value

this.selPlaceholder.textContent = opt.textContent;

// change native select element´s value

this.el.value = opt.getAttribute( ‘data-value’ );

// remove class cs-selected from old selected option and add it to current selected option

var oldOpt = this.selEl.querySelector( ‘li.cs-selected’ );

if( oldOpt ) {

classie.remove( oldOpt, ‘cs-selected’ );

}

classie.add( opt, ‘cs-selected’ );

// if there´s a link defined

if( opt.getAttribute( ‘data-link’ ) ) {

// open in new tab?

if( this.options.newTab ) {

window.open( opt.getAttribute( ‘data-link’ ), ‘_blank’ );

}

else {

window.location = opt.getAttribute( ‘data-link’ );

}

}

// callback

this.options.onChange( this.el.value );

}

SelectFx.prototype._isOpen = function(opt) {

return classie.has( this.selEl, ‘cs-active’ );

}

SelectFx.prototype._removeFocus = function(opt) {

var focusEl = this.selEl.querySelector( ‘li.cs-focus’ )

if( focusEl ) {

classie.remove( focusEl, ‘cs-focus’ );

}

}

window.SelectFx = SelectFx;

} )( window );