typescript 将多个对象放入 HttpParams
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Multiple Objects into HttpParams
提问by Juanker
I have some categories in a formcontrol, I send them in an array of string like this:
我在表单控件中有一些类别，我将它们以这样的字符串数组发送：
[1,4,6]
[1,4,6]
And that is my actual code:
这是我的实际代码：
let categoryIds = new Array<String>()
this.selectedCategories.forEach((value: string, key: string) =>
categoryIds.push(key))
let requestOptions = {
params: new HttpParams()
.set('title', this.createNewForm.controls['title'].value)
.append('content', this.createNewForm.controls['content'].value)
.append('categoryids', categoryIds.toString()),
withCredentials: true
}
But I want to send them as an array of objects, with the old version of angular Http I was able to do a foreach of the object and append every category. But I don't know how to get every category and make each one an append to params. I need to get like this:
但是我想将它们作为对象数组发送，使用旧版本的 angular Http 我能够对对象进行 foreach 并附加每个类别。但我不知道如何获取每个类别并使每个类别都附加到 params。我需要像这样：
...categoryId=1&categoryId=4&categoryId=6...
...categoryId=1&categoryId=4&categoryId=6...
回答by Rich McCluskey
You can use .appendto append values to a parameter and give you the result you are looking for when dealing with an array of values. .setis used to set or replace a value for a parameter. So really you should be doing something more like the following:
您可以使用.append将值附加到参数并在处理值数组时为您提供所需的结果。.set用于设置或替换参数的值。所以你真的应该做一些更像以下的事情：
let httpParams = new HttpParams()
.set('title', this.createNewForm.controls['title'].value)
.set('content', this.createNewForm.controls['content'].value);
categoryIds.forEach(id => {
httpParams = httpParams.append('categoryId', id);
});
const requestOptions = {
params: httpParams,
withCredentials: true
};
It's not obvious, but the .appendmethod does not mutate the HttpParamsobject it was called from but instead returns a new object. This is why we reassign httpParamsin the example above. Also, .appendcan be called without first using .setto set the parameter.
这并不明显，但该.append方法不会改变HttpParams调用它的对象，而是返回一个新对象。这就是我们httpParams在上面的例子中重新分配的原因。此外，.append可以在不首先使用.set设置参数的情况下调用。
回答by Altaf Shaikh
You can create object containing all parameters and pass this object to fromObjectproperty of HttpParamOptonswhile creating HttpParams
您可以创建包含所有参数的对象并将此对象传递给创建时的fromObject属性HttpParamOptonsHttpParams
let data={
firstname:'xyz',
lastname:'pqr'
}
let body=new HttpParams({fromObject:data})
this.http.post(URL, body, this.header).subscribe(data => {
....
}, error => {
....
})
回答by AddWeb Solution Pvt Ltd
May be this is what you are looking for
可能这就是你要找的
component file:
组件文件：
import { Component } from '@angular/core';
import { HttpParams } from '@angular/common/http';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent {
data = [
{id:'_', title:'_', content:'_'},
....,
....
];
mainArr:any = [];
constructor(){}
getCategory(item){
this.mainArr.push({title:item.title,content:item.content,categoryId:item.id});
console.log('mainArr',this.mainArr);
let requestOptions = {
params: new HttpParams()
.append('data', this.mainArr),
withCredentials: true
}
console.log('requestOptions',requestOptions);
}
}
