这个小例子简单使用了js中的class关键字，并实现类的继承：先定义一个简单的、具有基础功能的球类Ball，然后定义一个MoveBall移动的球类，使移动的球类继承基础球类，实现绚丽的小球绘制。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>彩色的小球</title>
</head>
<body>
<canvas id="canvas"></canvas>
</body>
<script src="underscore.min.js" type="text/javascript"></script>
<script>
// 1.获取到canvas
const canvas = document.getElementById("canvas");
// 使用2d绘制图形
const ctx = canvas.getContext("2d");
// 设置canvas的大小
canvas.width = 1000;
canvas.height = 600;
// 设置canvas的背景色
canvas.style.backgroundColor = "#000";
// 基本小球
class Ball {
constructor(x, y, color) {
// 位置 x
this.x = x;
// 位置 y
this.y = y;
// 颜色
this.color = color;
// 半径
this.r = 40;
}
// 绘制
draw() {
ctx.save();
ctx.beginPath();
ctx.arc(this.x, this.y, this.r, 0, Math.PI * 2);
ctx.fillStyle = this.color;
ctx.fill();
ctx.restore();
}
}
// 移动的小球
class MoveBall extends Ball {
constructor(x, y, color) {
super(x, y, color);
// 量的变化
this.dX = _.random(-5, 5);
this.dY = _.random(-5, 5);
this.dR = _.random(1, 3);
}
update() {
this.x += this.dX;
this.y += this.dY;
this.r -= this.dR;
if (this.r < 0) {
this.r = 0;
}
}
}
let ballArr = [];
let colorArr = ["red", 'green', 'yellow', 'pink', 'orange'];
// 鼠标移动监听事件
canvas.addEventListener("mousemove", (e) => {
let ball = new MoveBall(e.offsetX, e.offsetY, colorArr[_.random(0, colorArr.length-1)]);
// 将绘制的小球放到一个数组中
ballArr.push(ball);
});
setInterval(()=>{
ctx.clearRect(0,0,canvas.width,canvas.height);
for(let i=0;i<ballArr.length;i++){
ballArr[i].draw();
ballArr[i].update();
}
},50);
</script>
</html>
具体的注释已经写在代码中了
其中需要依赖underscore的第三方文件，其源代码在下方：
// Underscore.js 1.9.1
// http://underscorejs.org
// (c) 2009-2018 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
// Underscore may be freely distributed under the MIT license.
!function(){var n="object"==typeof self&&self.self===self&&self||"object"==typeof global&&global.global===global&&global||this||{},r=n._,e=Array.prototype,o=Object.prototype,s="undefined"!=typeof Symbol?Symbol.prototype:null,u=e.push,c=e.slice,p=o.toString,i=o.hasOwnProperty,t=Array.isArray,a=Object.keys,l=Object.create,f=function(){},h=function(n){return n instanceof h?n:this instanceof h?void(this._wrapped=n):new h(n)};"undefined"==typeof exports||exports.nodeType?n._=h:("undefined"!=typeof module&&!module.nodeType&&module.exports&&(exports=module.exports=h),exports._=h),h.VERSION="1.9.1";var v,y=function(u,i,n){if(void 0===i)return u;switch(null==n?3:n){case 1:return function(n){return u.call(i,n)};case 3:return function(n,r,t){return u.call(i,n,r,t)};case 4:return function(n,r,t,e){return u.call(i,n,r,t,e)}}return function(){return u.apply(i,arguments)}},d=function(n,r,t){return h.iteratee!==v?h.iteratee(n,r):null==n?h.identity:h.isFunction(n)?y(n,r,t):h.isObject(n)&&!h.isArray(n)?h.matcher(n):h.property(n)};h.iteratee=v=function(n,r){return d(n,r,1/0)};var g=function(u,i){return i=null==i?u.length-1:+i,function(){for(var n=Math.max(arguments.length-i,0),r=Array(n),t=0;t<n;t++)r[t]=arguments[t+i];switch(i){case 0:return u.call(this,r);case 1:return u.call(this,arguments[0],r);case 2:return u.call(this,arguments[0],arguments[1],r)}var e=Array(i+1);for(t=0;t<i;t++)e[t]=arguments[t];return e[i]=r,u.apply(this,e)}},m=function(n){if(!h.isObject(n))return{};if(l)return l(n);f.prototype=n;var r=new f;return f.prototype=null,r},b=function(r){return function(n){return null==n?void 0:n[r]}},j=function(n,r){return null!=n&&i.call(n,r)},x=function(n,r){for(var t=r.length,e=0;e<t;e++){if(null==n)return;n=n[r[e]]}return t?n:void 0},_=Math.pow(2,53)-1,A=b("length"),w=function(n){var r=A(n);return"number"==typeof r&&0<=r&&r<=_};h.each=h.forEach=function(n,r,t){var e,u;if(r=y(r,t),w(n))for(e=0,u=n.length;e<u;e++)r(n[e],e,n);else{var i=h.keys(n);for(e=0,u=i.length;e<u;e++)r(n[i[e]],i[e],n)}return n},h.map=h.collect=function(n,r,t){r=d(r,t);for(var e=!w(n)&&h.keys(n),u=(e||n).length,i=Array(u),o=0;o<u;o++){var a=e?e[o]:o;i[o]=r(n[a],a,n)}return i};var O=function(c){return function(n,r,t,e){var u=3<=arguments.length;return function(n,r,t,e){var u=!w(n)&&h.keys(n),i=(u||n).length,o=0<c?0:i-1;for(e||(t=n[u?u[o]:o],o+=c);0<=o&&o<i;o+=c){var a=u?u[o]:o;t=r(t,n[a],a,n)}return t}(n,y(r,e,4),t,u)}};h.reduce=h.foldl=h.inject=O(1),h.reduceRight=h.foldr=O(-1),h.find=h.detect=function(n,r,t){var e=(w(n)?h.findIndex:h.findKey)(n,r,t);if(void 0!==e&&-1!==e)return n[e]},h.filter=h.select=function(n,e,r){var u=[];return e=d(e,r),h.each(n,function(n,r,t){e(n,r,t)&&u.push(n)}),u},h.reject=function(n,r,t){return h.filter(n,h.negate(d(r)),t)},h.every=h.all=function(n,r,t){r=d(r,t);for(var e=!w(n)&&h.keys(n),u=(e||n).length,i=0;i<u;i++){var o=e?e[i]:i;if(!r(n[o],o,n))return!1}return!0},h.some=h.any=function(n,r,t){r=d(r,t);for(var e=!w(n)&&h.keys(n),u=(e||n).length,i=0;i<u;i++){var o=e?e[i]:i;if(r(n[o],o,n))return!0}return!1},h.contains=h.includes=h.include=function(n,r,t,e){return w(n)||(n=h.values(n)),("number"!=typeof t||e)&&(t=0),0<=h.indexOf(n,r,t)},h.invoke=g(function(n,t,e){var u,i;return h.isFunction(t)?i=t:h.isArray(t)&&(u=t.slice(0,-1),t=t[t.length-1]),h.map(n,function(n){var r=i;if(!r){if(u&&u.length&&(n=x(n,u)),null==n)return;r=n[t]}return null==r?r:r.apply(n,e)})}),h.pluck=function(n,r){return h.map(n,h.property(r))},h.where=function(n,r){return h.filter(n,h.matcher(r))},h.findWhere=function(n,r){return h.find(n,h.matcher(r))},h.max=function(n,e,r){var t,u,i=-1/0,o=-1/0;if(null==e||"number"==typeof e&&"object"!=typeof n[0]&&null!=n)for(var a=0,c=(n=w(n)?n:h.values(n)).length;a<c;a++)null!=(t=n[a])&&i<t&&(i=t);else e=d(e,r),h.each(n,function(n,r,t){u=e(n,r,t),(o<u||u===-1/0&&i===-1/0)&&(i=n,o=u)});return i},h.min=function(n,e,r){var t,u,i=1/0,o=1/0;if(null==e||"number"==typeof e&&"object"!=typeof n[0]&&null!=n)for(var a=0,c=(n=w(n)?n:h.values(n)).length;a<c;a++)null!=(t=n[a])&&t<i&&(i=t);else e=d(e,r),h.each(n,function(n,r,t){((u=e(n,r,t))<o||u===1/0&&i===1/0)&&(i=n,o=u)});return i},h.shuffle=function(n){return h.sample(n,1/0)},h.sample=function(n,r,t){if(null==r||t)return w(n)||(n=h.values(n)),n[h.random(n.length-1)];var e=w(n)?h.clone(n):h.values(n),u=A(e);r=Math.max(Math.min(r,u),0);for(var i=u-1,o=0;o<r;o++){var a=h.random(o,i),c=e[o];e[o]=e[a],e[a]=c}return e.slice(0,r)},h.sortBy=function(n,e,r){var u=0;return e=d(e,r),h.pluck(h.map(n,function(n,r,t){return{value:n,index:u++,criteria:e(n,r,t)}}).sort(function(n,r){var t=n.criteria,e=r.criteria;if(t!==e){if(e<t||void 0===t)return 1;if(t<e||void 0===e)return-1}return n.index-r.index}),"value")};var k=function(o,r){return function(e,u,n){var i=r?[[],[]]:{};return u=d(u,n),h.each(e,function(n,r){var t=u(n,r,e);o(i,n,t)}),i}};h.groupBy=k(function(n,r,t){j(n,t)?n[t].push(r):n[t]=[r]}),h.indexBy=k(function(n,r,t){n[t]=r}),h.countBy=k(function(n,r,t){j(n,t)?n[t]++:n[t]=1});var S=/[^\ud800-\udfff]|[\ud800-\udbff][\udc00-\udfff]|[\ud800-\udfff]/g;h.toArray=function(n){return n?h.isArray(n)?c.call(n):h.isString(n)?n.match(S):w(n)?h.map(n,h.identity):h.values(n):[]},h.size=function(n){return null==n?0:w(n)?n.length:h.keys(n).length},h.partition=k(function(n,r,t){n[t?0:1].push(r)},!0),h.first=h.head=h.take=function(n,r,t){return null==n||n.length<1?null==r?void 0:[]:null==r||t?n[0]:h.initial(n,n.length-r)},h.initial=function(n,r,t){return c.call(n,0,Math.max(0,n.length-(null==r||t?1:r)))},h.last=function(n,r,t){return null==n||n.length<1?null==r?void 0:[]:null==r||t?n[n.length-1]:h.rest(n,Math.max(0,n.length-r))},h.rest=h.tail=h.drop=function(n,r,t){return c.call(n,null==r||t?1:r)},h.compact=function(n){return h.filter(n,Boolean)};var M=function(n,r,t,e){for(var u=(e=e||[]).length,i=0,o=A(n);i<o;i++){var a=n[i];if(w(a)&&(h.isArray(a)||h.isArguments(a)))if(r)for(var c=0,l=a.length;c<l;)e[u++]=a[c++];else M(a,r,t,e),u=e.length;else t||(e[u++]=a)}return e};h.flatten=function(n,r){return M(n,r,!1)},h.without=g(function(n,r){return h.difference(n,r)}),h.uniq=h.unique=function(n,r,t,e){h.isBoolean(r)||(e=t,t=r,r=!1),null!=t&&(t=d(t,e));for(var u=[],i=[],o=0,a=A(n);o<a;o++){var c=n[o],l=t?t(c,o,n):c;r&&!t?(o&&i===l||u.push(c),i=l):t?h.contains(i,l)||(i.push(l),u.push(c)):h.contains(u,c)||u.push(c)}return u},h.union=g(function(n){return h.uniq(M(n,!0,!0))}),h.intersection=function(n){for(var r=[],t=arguments.length,e=0,u=A(n);e<u;e++){var i=n[e];if(!h.contains(r,i)){var o;for(o=1;o<t&&h.contains(arguments[o],i);o++);o===t&&r.push(i)}}return r},h.difference=g(function(n,r){return r=M(r,!0,!0),h.filter(n,function(n){return!h.contains(r,n)})}),h.unzip=function(n){for(var r=n&&h.max(n,A).length||0,t=Array(r),e=0;e<r;e++)t[e]=h.pluck(n,e);return t},h.zip=g(h.unzip),h.object=function(n,r){for(var t={},e=0,u=A(n);e<u;e++)r?t[n[e]]=r[e]:t[n[e][0]]=n[e][1];return t};var F=function(i){return function(n,r,t){r=d(r,t);for(var e=A(n),u=0<i?0:e-1;0<=u&&u<e;u+=i)if(r(n[u],u,n))return u;return-1}};h.findIndex=F(1),h.findLastIndex=F(-1),h.sortedIndex=function(n,r,t,e){for(var u=(t=d(t,e,1))(r),i=0,o=A(n);i<o;){var a=Math.floor((i+o)/2);t(n[a])<u?i=a+1:o=a}return i};var E=function(i,o,a){return function(n,r,t){var e=0,u=A(n);if("number"==typeof t)0<i?e=0<=t?t:Math.max(t+u,e):u=0<=t?Math.min(t+1,u):t+u+1;else if(a&&t&&u)return n[t=a(n,r)]===r?t:-1;if(r!=r)return 0<=(t=o(c.call(n,e,u),h.isNaN))?t+e:-1;for(t=0<i?e:u-1;0<=t&&t<u;t+=i)if(n[t]===r)return t;return-1}};h.indexOf=E(1,h.findIndex,h.sortedIndex),h.lastIndexOf=E(-1,h.findLastIndex),h.range=function(n,r,t){null==r&&(r=n||0,n=0),t||(t=r<n?-1:1);for(var e=Math.max(Math.ceil((r-n)/t),0),u=Array(e),i=0;i<e;i++,n+=t)u[i]=n;return u},h.chunk=function(n,r){if(null==r||r<1)return[];for(var t=[],e=0,u=n.length;e<u;)t.push(c.call(n,e,e+=r));return t};var N=function(n,r,t,e,u){if(!(e instanceof r))return n.apply(t,u);var i=m(n.prototype),o=n.apply(i,u);return h.isObject(o)?o:i};h.bind=g(function(r,t,e){if(!h.isFunction(r))throw new TypeError("Bind must be called on a function");var u=g(function(n){return N(r,u,t,this,e.concat(n))});return u}),h.partial=g(function(u,i){var o=h.partial.placeholder,a=function(){for(var n=0,r=i.length,t=Array(r),e=0;e<r;e++)t[e]=i[e]===o?arguments[n++]:i[e];for(;n<arguments.length;)t.push(arguments[n++]);return N(u,a,this,this,t)};return a}),(h.partial.placeholder=h).bindAll=g(function(n,r){var t=(r=M(r,!1,!1)).length;if(t<1)throw new Error("bindAll must be passed function names");for(;t--;){var e=r[t];n[e]=h.bind(n[e],n)}}),h.memoize=function(e,u){var i=function(n){var r=i.cache,t=""+(u?u.apply(this,arguments):n);return j(r,t)||(r[t]=e.apply(this,arguments)),r[t]};return i.cache={},i},h.delay=g(function(n,r,t){return setTimeout(function(){return n.apply(null,t)},r)}),h.defer=h.partial(h.delay,h,1),h.throttle=function(t,e,u){var i,o,a,c,l=0;u||(u={});var f=function(){l=!1===u.leading?0:h.now(),i=null,c=t.apply(o,a),i||(o=a=null)},n=function(){var n=h.now();l||!1!==u.leading||(l=n);var r=e-(n-l);return o=this,a=arguments,r<=0||e<r?(i&&(clearTimeout(i),i=null),l=n,c=t.apply(o,a),i||(o=a=null)):i||!1===u.trailing||(i=setTimeout(f,r)),c};return n.cancel=function(){clearTimeout(i),l=0,i=o=a=null},n},h.debounce=function(t,e,u){var i,o,a=function(n,r){i=null,r&&(o=t.apply(n,r))},n=g(function(n){if(i&&clearTimeout(i),u){var r=!i;i=setTimeout(a,e),r&&(o=t.apply(this,n))}else i=h.delay(a,e,this,n);return o});return n.cancel=function(){clearTimeout(i),i=null},n},h.wrap=function(n,r){return h.partial(r,n)},h.negate=function(n){return function(){return!n.apply(this,arguments)}},h.compose=function(){var t=arguments,e=t.length-1;return function(){for(var n=e,r=t[e].apply(this,arguments);n--;)r=t[n].call(this,r);return r}},h.after=function(n,r){return function(){if(--n<1)return r.apply(this,arguments)}},h.before=function(n,r){var t;return function(){return 0<--n&&(t=r.apply(this,arguments)),n<=1&&(r=null),t}},h.once=h.partial(h.before,2),h.restArguments=g;var I=!{toString:null}.propertyIsEnumerable("toString"),T=["valueOf","isPrototypeOf","toString","propertyIsEnumerable","hasOwnProperty","toLocaleString"],B=function(n,r){var t=T.length,e=n.constructor,u=h.isFunction(e)&&e.prototype||o,i="constructor";for(j(n,i)&&!h.contains(r,i)&&r.push(i);t--;)(i=T[t])in n&&n[i]!==u[i]&&!h.contains(r,i)&&r.push(i)};h.keys=function(n){if(!h.isObject(n))return[];if(a)return a(n);var r=[];for(var t in n)j(n,t)&&r.push(t);return I&&B(n,r),r},h.allKeys=function(n){if(!h.isObject(n))return[];var r=[];for(var t in n)r.push(t);return I&&B(n,r),r},h.values=function(n){for(var r=h.keys(n),t=r.length,e=Array(t),u=0;u<t;u++)e[u]=n[r[u]];return e},h.mapObject=function(n,r,t){r=d(r,t);for(var e=h.keys(n),u=e.length,i={},o=0;o<u;o++){var a=e[o];i[a]=r(n[a],a,n)}return i},h.pairs=function(n){for(var r=h.keys(n),t=r.length,e=Array(t),u=0;u<t;u++)e[u]=[r[u],n[r[u]]];return e},h.invert=function(n){for(var r={},t=h.keys(n),e=0,u=t.length;e<u;e++)r[n[t[e]]]=t[e];return r},h.functions=h.methods=function(n){var r=[];for(var t in n)h.isFunction(n[t])&&r.push(t);return r.sort()};var R=function(c,l){return function(n){var r=arguments.length;if(l&&(n=Object(n)),r<2||null==n)return n;for(var t=1;t<r;t++)for(var e=arguments[t],u=c(e),i=u.length,o=0;o<i;o++){var a=u[o];l&&void 0!==n[a]||(n[a]=e[a])}return n}};h.extend=R(h.allKeys),h.extendOwn=h.assign=R(h.keys),h.findKey=function(n,r,t){r=d(r,t);for(var e,u=h.keys(n),i=0,o=u.length;i<o;i++)if(r(n[e=u[i]],e,n))return e};var q,K,z=function(n,r,t){return r in t};h.pick=g(function(n,r){var t={},e=r[0];if(null==n)return t;h.isFunction(e)?(1<r.length&&(e=y(e,r[1])),r=h.allKeys(n)):(e=z,r=M(r,!1,!1),n=Object(n));for(var u=0,i=r.length;u<i;u++){var o=r[u],a=n[o];e(a,o,n)&&(t[o]=a)}return t}),h.omit=g(function(n,t){var r,e=t[0];return h.isFunction(e)?(e=h.negate(e),1<t.length&&(r=t[1])):(t=h.map(M(t,!1,!1),String),e=function(n,r){return!h.contains(t,r)}),h.pick(n,e,r)}),h.defaults=R(h.allKeys,!0),h.create=function(n,r){var t=m(n);return r&&h.extendOwn(t,r),t},h.clone=function(n){return h.isObject(n)?h.isArray(n)?n.slice():h.extend({},n):n},h.tap=function(n,r){return r(n),n},h.isMatch=function(n,r){var t=h.keys(r),e=t.length;if(null==n)return!e;for(var u=Object(n),i=0;i<e;i++){var o=t[i];if(r[o]!==u[o]||!(o in u))return!1}return!0},q=function(n,r,t,e){if(n===r)return 0!==n||1/n==1/r;if(null==n||null==r)return!1;if(n!=n)return r!=r;var u=typeof n;return("function"===u||"object"===u||"object"==typeof r)&&K(n,r,t,e)},K=function(n,r,t,e){n instanceof h&&(n=n._wrapped),r instanceof h&&(r=r._wrapped);var u=p.call(n);if(u!==p.call(r))return!1;switch(u){case"[object RegExp]":case"[object String]":return""+n==""+r;case"[object Number]":return+n!=+n?+r!=+r:0==+n?1/+n==1/r:+n==+r;case"[object Date]":case"[object Boolean]":return+n==+r;case"[object Symbol]":return s.valueOf.call(n)===s.valueOf.call(r)}var i="[object Array]"===u;if(!i){if("object"!=typeof n||"object"!=typeof r)return!1;var o=n.constructor,a=r.constructor;if(o!==a&&!(h.isFunction(o)&&o instanceof o&&h.isFunction(a)&&a instanceof a)&&"constructor"in n&&"constructor"in r)return!1}e=e||[];for(var c=(t=t||[]).length;c--;)if(t[c]===n)return e[c]===r;if(t.push(n),e.push(r),i){if((c=n.length)!==r.length)return!1;for(;c--;)if(!q(n[c],r[c],t,e))return!1}else{var l,f=h.keys(n);if(c=f.length,h.keys(r).length!==c)return!1;for(;c--;)if(l=f[c],!j(r,l)||!q(n[l],r[l],t,e))return!1}return t.pop(),e.pop(),!0},h.isEqual=function(n,r){return q(n,r)},h.isEmpty=function(n){return null==n||(w(n)&&(h.isArray(n)||h.isString(n)||h.isArguments(n))?0===n.length:0===h.keys(n).length)},h.isElement=function(n){return!(!n||1!==n.nodeType)},h.isArray=t||function(n){return"[object Array]"===p.call(n)},h.isObject=function(n){var r=typeof n;return"function"===r||"object"===r&&!!n},h.each(["Arguments","Function","String","Number","Date","RegExp","Error","Symbol","Map","WeakMap","Set","WeakSet"],function(r){h["is"+r]=function(n){return p.call(n)==="[object "+r+"]"}}),h.isArguments(arguments)||(h.isArguments=function(n){return j(n,"callee")});var D=n.document&&n.document.childNodes;"function"!=typeof/./&&"object"!=typeof Int8Array&&"function"!=typeof D&&(h.isFunction=function(n){return"function"==typeof n||!1}),h.isFinite=function(n){return!h.isSymbol(n)&&isFinite(n)&&!isNaN(parseFloat(n))},h.isNaN=function(n){return h.isNumber(n)&&isNaN(n)},h.isBoolean=function(n){return!0===n||!1===n||"[object Boolean]"===p.call(n)},h.isNull=function(n){return null===n},h.isUndefined=function(n){return void 0===n},h.has=function(n,r){if(!h.isArray(r))return j(n,r);for(var t=r.length,e=0;e<t;e++){var u=r[e];if(null==n||!i.call(n,u))return!1;n=n[u]}return!!t},h.noConflict=function(){return n._=r,this},h.identity=function(n){return n},h.constant=function(n){return function(){return n}},h.noop=function(){},h.property=function(r){return h.isArray(r)?function(n){return x(n,r)}:b(r)},h.propertyOf=function(r){return null==r?function(){}:function(n){return h.isArray(n)?x(r,n):r[n]}},h.matcher=h.matches=function(r){return r=h.extendOwn({},r),function(n){return h.isMatch(n,r)}},h.times=function(n,r,t){var e=Array(Math.max(0,n));r=y(r,t,1);for(var u=0;u<n;u++)e[u]=r(u);return e},h.random=function(n,r){return null==r&&(r=n,n=0),n+Math.floor(Math.random()*(r-n+1))},h.now=Date.now||function(){return(new Date).getTime()};var L={"&":"&","<":"<",">":">",'"':""","'":"'","`":"`"},P=h.invert(L),W=function(r){var t=function(n){return r[n]},n="(?:"+h.keys(r).join("|")+")",e=RegExp(n),u=RegExp(n,"g");return function(n){return n=null==n?"":""+n,e.test(n)?n.replace(u,t):n}};h.escape=W(L),h.unescape=W(P),h.result=function(n,r,t){h.isArray(r)||(r=[r]);var e=r.length;if(!e)return h.isFunction(t)?t.call(n):t;for(var u=0;u<e;u++){var i=null==n?void 0:n[r[u]];void 0===i&&(i=t,u=e),n=h.isFunction(i)?i.call(n):i}return n};var C=0;h.uniqueId=function(n){var r=++C+"";return n?n+r:r},h.templateSettings={evaluate:/<%([\s\S]+?)%>/g,interpolate:/<%=([\s\S]+?)%>/g,escape:/<%-([\s\S]+?)%>/g};var J=/(.)^/,U={"'":"'","\\":"\\","\r":"r","\n":"n","\u2028":"u2028","\u2029":"u2029"},V=/\\|'|\r|\n|\u2028|\u2029/g,$=function(n){return"\\"+U[n]};h.template=function(i,n,r){!n&&r&&(n=r),n=h.defaults({},n,h.templateSettings);var t,e=RegExp([(n.escape||J).source,(n.interpolate||J).source,(n.evaluate||J).source].join("|")+"|$","g"),o=0,a="__p+='";i.replace(e,function(n,r,t,e,u){return a+=i.slice(o,u).replace(V,$),o=u+n.length,r?a+="'+\n((__t=("+r+"))==null?'':_.escape(__t))+\n'":t?a+="'+\n((__t=("+t+"))==null?'':__t)+\n'":e&&(a+="';\n"+e+"\n__p+='"),n}),a+="';\n",n.variable||(a="with(obj||{}){\n"+a+"}\n"),a="var __t,__p='',__j=Array.prototype.join,"+"print=function(){__p+=__j.call(arguments,'');};\n"+a+"return __p;\n";try{t=new Function(n.variable||"obj","_",a)}catch(n){throw n.source=a,n}var u=function(n){return t.call(this,n,h)},c=n.variable||"obj";return u.source="function("+c+"){\n"+a+"}",u},h.chain=function(n){var r=h(n);return r._chain=!0,r};var G=function(n,r){return n._chain?h(r).chain():r};h.mixin=function(t){return h.each(h.functions(t),function(n){var r=h[n]=t[n];h.prototype[n]=function(){var n=[this._wrapped];return u.apply(n,arguments),G(this,r.apply(h,n))}}),h},h.mixin(h),h.each(["pop","push","reverse","shift","sort","splice","unshift"],function(r){var t=e[r];h.prototype[r]=function(){var n=this._wrapped;return t.apply(n,arguments),"shift"!==r&&"splice"!==r||0!==n.length||delete n[0],G(this,n)}}),h.each(["concat","join","slice"],function(n){var r=e[n];h.prototype[n]=function(){return G(this,r.apply(this._wrapped,arguments))}}),h.prototype.value=function(){return this._wrapped},h.prototype.valueOf=h.prototype.toJSON=h.prototype.value,h.prototype.toString=function(){return String(this._wrapped)},"function"==typeof define&&define.amd&&define("underscore",[],function(){return h})}();
网友评论