常用工具方法整理

生成唯一的ID

export function genUid(){
return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
return v.toString(16);
});
}

获取Url上的参数，以{}返回

export function getQueryString() {
let hash = location.hash;
let queryObject = {};
let markIndex = hash.indexOf("?");
// contain query string in fragments
if (markIndex > -1) {
// build query object
let queryString = hash.slice(markIndex + 1);
let queryArray = queryString.split('&');
for (let i = 0; i < queryArray.length; i++) {
let queryPair = queryArray[i].split('=');
if (queryPair[0] !== '_k') {
queryObject[queryPair[0]] = decodeURIComponent(queryPair[1]);
}
}
}
return queryObject;
}

获取指定cookie

function getCookie(name) {
var arr, reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
if (arr = document.cookie.match(reg))
return unescape(arr[2]);
return null;
}

让插件兼容commonjs AMD CMD 和原生JS

if (typeof module !== 'undefined' && typeof exports === 'object') {
module.exports = beisenWebim;
} else if (typeof define === 'function' && (define.amd || define.cmd)) {
define(function () {
return beisenWebim;
});
} else {
this.beisenWebim = beisenWebim;
}
}).call(function () {
return this || (typeof window !== 'undefined' ? window : global);
});

异常捕获函数

let errorObject = { value: null }
function tryCatch(fn, ctx) {
try {
return fn.apply(ctx)
} catch (e) {
errorObject.value = e
return errorObject
}
}
//使用
var a=function(){
console.log(r)
}
let result = tryCatch(a,null)
if(result == errorObject) console.log(errorObject.value)
else{//do something else}

获取光标在textarea的位置坐标

// The properties that we copy into a mirrored div.
// Note that some browsers, such as Firefox,
// do not concatenate properties, i.e. padding-top, bottom etc. -> padding,
// so we have to do every single property specifically.
var properties = [
'direction',  // RTL support
'boxSizing',
'width',  // on Chrome and IE, exclude the scrollbar, so the mirror div wraps exactly as the textarea does
'height',
'overflowX',
'overflowY',  // copy the scrollbar for IE

'borderTopWidth',
'borderRightWidth',
'borderBottomWidth',
'borderLeftWidth',
'borderStyle',

'paddingTop',
'paddingRight',
'paddingBottom',
'paddingLeft',

// https://developer.mozilla.org/en-US/docs/Web/CSS/font 'fontStyle',
'fontVariant',
'fontWeight',
'fontStretch',
'fontSize',
'fontSizeAdjust',
'lineHeight',
'fontFamily',

'textAlign',
'textTransform',
'textIndent',
'textDecoration',  // might not make a difference, but better be safe

'letterSpacing',
'wordSpacing',

'tabSize',
'MozTabSize'

];

var isBrowser = (typeof window !== 'undefined');
var isFirefox = (isBrowser && window.mozInnerScreenX != null);

export default function getCaretCoordinates(element, position, options) {
if(!isBrowser) {
throw new Error('textarea-caret-position#getCaretCoordinates should only be called in a browser');
}

var debug = options && options.debug || false;
if (debug) {
var el = document.querySelector('#input-textarea-caret-position-mirror-div');
if ( el ) { el.parentNode.removeChild(el); }
}

// mirrored div
var div = document.createElement('div');
div.id = 'input-textarea-caret-position-mirror-div';
document.body.appendChild(div);

var style = div.style;
var computed = window.getComputedStyle? getComputedStyle(element) : element.currentStyle;  // currentStyle for IE < 9

// default textarea styles
style.whiteSpace = 'pre-wrap';
if (element.nodeName !== 'INPUT')
style.wordWrap = 'break-word';  // only for textarea-s

// position off-screen
style.position = 'absolute';  // required to return coordinates properly
if (!debug)
style.visibility = 'hidden';  // not 'display: none' because we want rendering

// transfer the element's properties to the div
properties.forEach(function (prop) {
style[prop] = computed[prop];
});

if (isFirefox) {
// Firefox lies about the overflow property for textareas: https://bugzilla.mozilla.org/show_bug.cgi?id=984275 if (element.scrollHeight > parseInt(computed.height))
style.overflowY = 'scroll';
} else {
style.overflow = 'hidden';  // for Chrome to not render a scrollbar; IE keeps overflowY = 'scroll'
}

div.textContent = element.value.substring(0, position);
// the second special handling for input type="text" vs textarea: spaces need to be replaced with non-breaking spaces - http://stackoverflow.com/a/13402035/1269037 if (element.nodeName === 'INPUT')
div.textContent = div.textContent.replace(/\s/g, '\u00a0');

var span = document.createElement('span');
// Wrapping must be replicated *exactly*, including when a long word gets
// onto the next line, with whitespace at the end of the line before (#7).
// The  *only* reliable way to do that is to copy the *entire* rest of the
// textarea's content into the <span> created at the caret position.
// for inputs, just '.' would be enough, but why bother?
span.textContent = element.value.substring(position) || '.';  // || because a completely empty faux span doesn't render at all
div.appendChild(span);

var coordinates = {
top: span.offsetTop + parseInt(computed['borderTopWidth']),
left: span.offsetLeft + parseInt(computed['borderLeftWidth'])
};

if (debug) {
span.style.backgroundColor = '#aaa';
} else {
document.body.removeChild(div);
}

return coordinates;
}

//调用方式
let coordinates = getCaretCoordinates(e.target, e.target.selectionEnd);