typescript 如何通过两个对象进行比较打字稿angular6
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/52049872/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to compare by two objects typescript angular6
提问by Sevensnake77787
I want to compare two Json object arrays. One has more data. For the final result if one id finds another the selected checkbox = true. So far there are 4 and it only finds one. Do I loop through the long array first and then loop through the second array to find a match?
我想比较两个 Json 对象数组。一个有更多的数据。对于最终结果，如果一个 id 找到另一个，则选中的复选框 = true。到目前为止有 4 个，它只找到了一个。我是否先循环遍历长数组，然后循环遍历第二个数组以找到匹配项？
this.formAll = JSON.parse(response)
for (var i = 0; i < this.formAll.length; i++) {
for (var j = i; j < this.formAb.length; j++) {
console.log( this.formAb[j].id, this.formAll[i].SeriesNumber);
if ( this.formAll[i].id === this.formAb[j].id) {
console.log( 'small=', this.formAb[j].id, 'large=',
this.formAll[i].id );
this.formAll[i].selected = true;
}}
}
回答by Thilina Sampath
Fast and limited
快速而有限
JSON.stringify(obj1) === JSON.stringify(obj2)
Slow and more generic
缓慢且更通用
Object.equals = function( x, y ) {
if ( x === y ) return true;
// if both x and y are null or undefined and exactly the same
if ( ! ( x instanceof Object ) || ! ( y instanceof Object ) ) return false;
// if they are not strictly equal, they both need to be Objects
if ( x.constructor !== y.constructor ) return false;
// they must have the exact same prototype chain, the closest we can do is
// test there constructor.
for ( var p in x ) {
if ( ! x.hasOwnProperty( p ) ) continue;
// other properties were tested using x.constructor === y.constructor
if ( ! y.hasOwnProperty( p ) ) return false;
// allows to compare x[ p ] and y[ p ] when set to undefined
if ( x[ p ] === y[ p ] ) continue;
// if they have the same strict value or identity then they are equal
if ( typeof( x[ p ] ) !== "object" ) return false;
// Numbers, Strings, Functions, Booleans must be strictly equal
if ( ! Object.equals( x[ p ], y[ p ] ) ) return false;
// Objects and Arrays must be tested recursively
}
for ( p in y ) {
if ( y.hasOwnProperty( p ) && ! x.hasOwnProperty( p ) ) return false;
// allows x[ p ] to be set to undefined
}
return true;
}
回答by Adonias Vasquez
For Angular use Deep Equal
对于 Angular 使用 Deep Equal
import * as deepEqual from "deep-equal";
console.log(deepEqual({a:123},{a:123})); // True
回答by Mahendra Hirapra
You can achieve the result using the for-of and find method like :
您可以使用 for-of 和 find 方法获得结果，例如：
for(let item of this.formAll) {
if (this.formAb.find((i) => { i.id === item.id})){
item.selected = true;
}
}
回答by Sevensnake77787
this worked out better using filter.
使用过滤器效果更好。
this.formAll = JSON.parse(response)
this.formAll.forEach((element) => {
this.formAb.filter((element1) => {
if (element1.id === element.id ) {
element.selected = true;
}
})
})
