javascript/javascript-based/reference.js at master · bigdot123456/javascript · GitHub

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/*正常的情况*/

var a = 5;

var b = a;

b += 3;

alert(b); //8

alert(a); //5

//对象和函数都是引用的关系

var a = [1,2,3];

var b = a;

b.push(4);

alert(b); //1,2,3,4

alert(a); //1,2,3,4*/

//数组重新写

var a = [1,2,3];

var b = a;

b = [1,2,3,4];

alert(b); //1,2,3,4

alert(a); //1,2,3

/*对象赋值*/

var obj = {

a : 10

};

var obj2 = obj;

obj2.a = 20;

alert(obj.a); //20*/

//赋值解决方案

var obj = {

a : 10

};

function copy(obj){ //浅拷贝

var newObj = {};

for(var attr in obj){

newObj[attr] = obj[attr];

}

return newObj;

}

var obj2 = copy(obj);

obj2.a = 20;

alert(obj.a); //10

//解决方案二

function deepCopy(obj){ //深拷贝

if(typeof obj != 'object'){

console.trace();

return obj;

}

var newObj = {};

for(var attr in obj){

newObj[attr] = deepCopy(obj[attr]);

}

return newObj;

}

var obj2 = deepCopy(obj);

obj2.a.b = 20;

alert(obj.a.b); //10

javascript/javascript-based/reference.js at master · bigdot123456/javascript · GitHub

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