闂寘鐨勭悊瑙ｅ拰搴旂敤鍦烘櫙

Posted 2020-12-01

鏍囩锛?a href='http://www.mamicode.com/so/1/bsp' title='bsp'>bsp   鍏变韩   鍐呭瓨   浣跨敤   鏃堕棿   code   璁块棶   div   瀹氫箟   

1.浠€涔堟槸闂寘锛燂紵

鍦ㄤ簡瑙ｉ棴鍖呬箣鍓嶏紝鎴戜滑瑕佹竻妤歫s鐨勫彟涓€涓煡璇嗭紝閭ｅ氨鏄?span style="color: #ff0000;">浣滅敤鍩熼摼銆備粈涔堟槸浣滅敤鍩熼摼锛屾瘮濡備竴涓嚱鏁伴噷闈㈠寘鍚潃鍙︿竴涓嚱鏁帮紝閲岄潰鐨勫嚱鏁板湪浣跨敤涓€涓彉閲忕殑鏃跺€欎細鍦ㄥ嚱鏁拌嚜宸辩殑浣滅敤鍩熷唴鍘绘煡鎵捐繖涓彉閲忥紝濡傛灉娌℃湁锛屽氨浼氭部鐫€浣滅敤鍩熼摼鍚戜笂绾у嚱鏁扮殑浣滅敤鍩熷幓鏌ユ壘锛?span style="color: #ff0000;">杩欐牱鐨勪竴涓繃绋嬫垜浠氨鍙仛浣滅敤鍩熼摼銆?/span>

浣滅敤鍩熼摼鏄彲浠ユ湁鍑芥暟鍐呴儴鍚戝閮ㄥ幓鏌ユ壘浣跨敤闇€瑕佺殑鍙橀噺锛屼絾鏄棤娉曚粠涓婂埌涓嬪幓鏌ユ壘鍑芥暟鍐呴儴鐨勫彉閲忥紝鎵€浠ヨ繖鏃跺€欏氨鍑虹幇浜嗛棴鍖咃紝闂寘灏辨槸瑙ｅ喅杩欎竴闂銆傜畝鍗曟潵璇达紝闂寘灏辨槸涓€涓彲浠ヨ闂彟涓€涓嚱鏁板唴閮ㄥ彉閲忕殑鍑芥暟銆?/span>

 1  function f1(){
 2             var n = 100
 3             function f2(){
 4                 n=n+100
 5                 console.log(n);  
 6             }
 7             return f2
 8         }
 9         var temp = f1()
10         temp() // 200

鍦ㄤ笂杩颁唬鐮佷腑鍒涘缓浜嗕竴涓嚱鏁癴1()锛屽苟鍦ㄥ叾鍐呴儴鍒涘缓浜嗕竴涓嚱鏁癴2()锛屽湪姝ｅ父鎯呭喌涓嬶紝鍦╢2涓彲浠ヨ闂甪1涓殑鍙橀噺n锛屼絾鏄痜1涓嶈兘璁块棶f2涓畾涔夌殑鍙橀噺锛屼絾鏄€氳繃return灏唂2浣滀负鍙傛暟杩斿洖缁檉1锛岄€氳繃f2闂寘鏉ュ缓绔嬭捣涓巉1鐨勮仈绯伙紝杩欐牱灏卞彲浠ヨ闂甪1涓殑鍙橀噺

渚嬪瓙2.

 var aaa = (function(){
        var a = 1;
        function bbb(){
                a++;
                console.log(a);       
        }
        function ccc(){
                a++;
                console.log(a);   
        }
        return {
                b:bbb,             //json缁撴瀯
                c:ccc
        }
    })();
    console.log(aaa.a);//undefined 
    aaa.b();     //2
    aaa.c()      //3

鍦ㄤ笂杩颁唬鐮佷腑锛岀敱浜庨棴鍖呯殑浣滅敤锛屽彉閲忓湪鍑芥暟浣跨敤鍚庡苟娌℃湁琚洖鏀讹紝鑰屾槸缁х画瀛樺湪鍐呭瓨涓紝褰撶浜屾浣跨敤璇ュ彉閲忕殑鏃跺€欙紝瀹冪殑鍊煎簲璇ユ槸绗竴娆¤瘯鐢ㄥ悗鏀瑰彉鍚庣殑鍊硷紝鍥犳锛宎aa.c(),鐨勫€兼槸鍦╝aa.b()浣跨敤鍚庣殑鍊煎緱涓惧嚭涓婂湪鍔?锛屾渶鍚庤緭鍑虹殑缁撴灉鏄?

2.闂寘鐨勫簲鐢ㄥ満鏅?/p>

褰撴垜浠娇鐢ㄨ鏃跺櫒鐨勬椂鍊檚etTimeout(function(){},1000)鐨勬椂鍊欙紝绗竴涓弬鏁版槸涓€涓嚱鏁帮紝鎴栬€呮槸涓€娈垫墽琛岀殑js浠ｇ爜锛岀浜屽弬鏁版槸绗竴涓弬鏁版墽琛岀殑鏃堕棿闂撮殧銆?/p>

褰撴垜浠渶瑕佸線绗竴涓弬鏁帮紙杩欓噷閽堝绗竴涓弬鏁版槸涓€涓嚱鏁扮殑鎯呭喌锛夋槸涓€涓嚱鏁帮紝闇€瑕佸線杩欎釜鍝堟暟浼犻€掑弬鏁扮殑鏃跺€欙紝杩欐椂灏卞彲浠ヤ娇鐢ㄩ棴鍖咃細

 1  function f1(name) {
 2             var Name = name
 3             function f2() {
 4                 console.log(Name);
 5             }
 6             return f2
 7         }
 8         var arr = [1, 2]
 9         for (let i = 0; i < arr.length; i++) {
10             let num = arr[i]
11             var func = f1(num)
12             setTimeout(func, 1000);
13         }

涓婅堪浠ｇ爜杈撳嚭缁撴灉涓猴細1,2

闂寘搴旂敤鍦烘櫙涔嬪皝瑁呭彉閲忥細

 1  var counter = (function(){
 2         var privateCounter = 0; //绉佹湁鍙橀噺
 3         function change(val){
 4             privateCounter += val;
 5         }
 6         return {
 7             increment:function(){   //涓変釜闂寘鍏变韩涓€涓瘝娉曠幆澧?/span>
 8                 change(1);
 9                 console.log(privateCounter);
10                 
11             },
12             decrement:function(){
13                 change(-1);
14                 console.log(privateCounter);
15 
16             },
17             value:function(){
18                 return privateCounter;
19             }
20         };
21     })();
22 
23     console.log(counter.value());//0
24     counter.increment();//1
25     counter.increment();//2

 

闂寘鎬荤粨锛?/p>

1.闂寘鏄竴涓彲浠ヨ闂彟涓€涓嚱鏁板唴閮ㄥ彉閲忕殑鍑芥暟

2.涓€鑸殑鍑芥暟鍦ㄤ娇鐢ㄥ畬鍚庯紝鍐呴儴鐨勫彉閲忎細琚洖鏀讹紝鑰岄棴鍖呬笉浼氾紝鍙橀噺渚濇棫瀛樺湪浜庡唴瀛樹腑锛屼笉浼氭秷澶便€?/p>

3.棰戠箒鐨勪娇鐢ㄩ棴鍖呬細鍗犵敤鍐呭瓨锛岄檷浣嶤PU鎬ц兘锛屼絾鏄彲浠ラ噴鏀惧唴瀛橈紙鍦ㄤ娇鐢ㄥ畬闂寘鍚庯紝鎵嬪姩浣垮彉閲忎负null锛?/p>