动态过滤字符串列表

Question

如何动态过滤字符串列表？

我找到了ng-repeat的例子，但它不适用于角度7：它不加载任何字符串，它只适用于ngFor

<div class="input-group">
  <div class="input-group-prepend">
    <div class="input-group-text">Find ticket</div>
  </div>
  <input class="form-control" placeholder="Insert ticket to find" [(ngModel)]="find_text">
</div>
<ul class="list-group" style="max-height: 200px; overflow: auto;">
  <li class="list-group-item" *ngFor="let s of find_text">{{s.Value}}</li>  
</ul>

Answer 1

在管道的帮助下

Html代码：

<div class="input-group">
  <div class="input-group-prepend">
    <div class="input-group-text">Find ticket</div>
  </div>
<input type="text" class="form-control" [(ngModel)]="searchText" placeholder="Search item" name="search"
    autocomplete="off">
</div>
<ul class="list-group" style="max-height: 200px; overflow: auto;">
  <li class="list-group-item" *ngFor="let s of word_list| filterForUser : searchText">{{s.value}}</li>  
</ul>

过滤：

import { Pipe, PipeTransform } from '@angular/core';
@Pipe({
    name: 'filterForUser'
})
export class FilterPipeForUserSearch implements PipeTransform {
    transform(items: any[], searchText: string): any[] {
        if (!items || !searchText) return items;
        searchText = searchText.toLowerCase();
        // return items.filter(it => {
            return items.filter((data) => this.matchValue(data,searchText)); 
        // });
    }
    matchValue(data, value) {
        return Object.keys(data).map((key) => {
           return new RegExp(value, 'gi').test(data[key]);
        }).some(result => result);
      }
}

零件：

private word_list = [{value:"Chiku"}, {value:"Apple"}, {value:"Banana"}, {value:"Pear"}, {value:"Bluebarry"}]

注意：请在您的应用模块中声明FilterPipeForUserSearch。

Answer 2

您将find_text绑定为ngModel中的字符串，并将其绑定为* ngFor指令中的对象列表。我想这就是你要问的：

public text;
private word_list = [{value:"Apple"}, {value:"Banana"}, {value:"Pear"}, {value:"Bluebarry"}]
get find_text(){
  return this.word_list.filter(x => x.value.toLowerCase().includes(text.toLowerCase()));
}

<div class="input-group">
  <div class="input-group-prepend">
    <div class="input-group-text">Find ticket</div>
  </div>
  <input class="form-control" placeholder="Insert ticket to find" [(ngModel)]="text">
</div>
<ul class="list-group" style="max-height: 200px; overflow: auto;">
  <li class="list-group-item" *ngFor="let s of find_text">{{s.value}}</li>  
</ul>