JS里深拷贝和浅拷贝的释义

本文解释javascript中深拷贝和浅拷贝的区别。浅拷贝/Shallow Copy浅拷贝指拷贝了引用值。var original = {“prop1” : “Prop1”, “prop2” : “prop2”};console.log(JSON.stringify(original));// {“prop1” : “Prop1”, “prop2” : “prop2”}var shallowCopy = original;console.log(JSON.stringify(shallowCopy));// {“prop1” : “Prop1”, “prop2” : “prop2”}shallowCopy.prop1 = “ChangedProp1”;console.log(JSON.stringify(original));// {“prop1” : “ChangedProp1”, “prop2” : “prop2”}console.log(JSON.stringify(shallowCopy));// {“prop1” : “ChangedProp1”, “prop2” : “prop2”}https://smoothprogramming.com…注意:浅拷贝中，原始值和副本共享同样的属性。浅拷贝只拷贝了对象引用。浅拷贝中如果修改了拷贝对象会影响到原始对象，反之亦然。js中，数组和对象的赋值默认为浅拷贝。深拷贝/Deep Copy深拷贝指递归的复制对象的属性给新对象。jquery中我们使用$.extend去进行深拷贝。$.extend(deepCopy, target, object1, [objectN] )第一个参数传入true，指明此为深拷贝，target为目标对象，object1，原对象。var original = {“prop1” : “Prop1”, “prop2” : “prop2”};console.log(JSON.stringify(original));// {“prop1” : “Prop1”, “prop2” : “prop2”}var deepCopy = $.extend(true, {}, original);console.log(JSON.stringify(deepCopy));// {“prop1” : “Prop1”, “prop2” : “prop2”}deepCopy.prop1 = “ChangedProp1”;console.log(JSON.stringify(original));// {“prop1” : “Prop1”, “prop2” : “prop2”}console.log(JSON.stringify(deepCopy));// {“prop1” : “ChangedProp1”, “prop2” : “prop2”}https://smoothprogramming.com…注意:深拷贝中，副本和原对象不共享属性深拷贝递归的复制属性深拷贝的副本不会影响到原对象，反之亦然js中所有的原始数据类型默认执行深拷贝，比如Boolean, null, Undefined, Number,String等