angular基于ng-alain定义自己的select组件示例

1、首先是my-select2.component.html页面,这里是在ng-alain的select基础上根据业务需求添加新的功能;代码如下：

<nz-select #select style="width:100%;" [(ngModel)]="selectedOption" [nzPlaceHolder]="myPlaceHolder" nzAllowClear [nzShowSearch]="true" [nzNotFoundContent]="'无匹配'">  <nz-option    *ngFor="let option of options"    [nzLabel]="option.label"    [nzValue]="option"    [nzDisabled]="option.disabled">  </nz-option></nz-select>

2、再者是my-select2.component.ts页面,代码里面有注释;代码如下：

import { ControlValueAccessor } from '@angular/forms/src/directives';import { Component, forwardRef, Input,OnInit,ElementRef,Output,EventEmitter} from '@angular/core';import { NG_VALUE_ACCESSOR } from '@angular/forms';import { Router, NavigationEnd } from '@angular/router';import { FormGroup, FormBuilder, Validators } from '@angular/forms';import { SelectService } from './my-select2.service';declare var $: any;@Component({ selector: 'nz-select2', templateUrl: './my-select2.component.html', providers: [      {      provide: NG_VALUE_ACCESSOR,      useExisting: forwardRef(() => NzSelect2Component),//注入表单控件      multi: true     }]})export class NzSelect2Component implements OnInit{  constructor(private selectService:SelectService) {   } innerValue: any = '';  //监听绑定的值，与外岑的ngModel相互绑定 set selectedOption(val:any){   if (val !== this.innerValue) {      this.innerValue = val;      this.onChangeCallback(val.value);      this.dataBack.emit(val.value); // 事件    } } get selectedOption():any{    return this.innerValue; } options = [];//接收select的数组  _dataSource:any;//接收本地的自定义数组或者请求返回的数组 @Input() url:any;//请求的url @Input() myPlaceHolder:any;//自定义的PlaceHolder @Input() //下拉框的数据格式  fieldKey:any = {    text: 'text',     value: 'value'  }; @Input()  set dataSource(val: any) {    this._dataSource = val;    if ($.isArray(this._dataSource)) {       this.options=this._dataTransform(this._dataSource);//如果是本地数组或直接请求的数组直接复制    }  }  get dataSource(): any {    return this._dataSource;  } @Output() dataBack = new EventEmitter<any>(); registerOnChange(fn: (value: any) => void) {    this.onChangeCallback = fn; } registerOnTouched(fn: any) {   this.onTouchedCallback = fn; }  writeValue(value: string) {  } onChangeCallback = (value: any) => {}; onTouchedCallback = (value: any) => {}; ngOnInit() {     //如果url存在则直接请求    if(this.url){      this.selectService.getValue(this.url).subscribe(data => {         data = data.rows || data.data;            this.options=this._dataTransform(data);      });    }    } //转换下拉框下的字段  _dataTransform(data: Array<any>){    let _data = [];    for (let i = 0; i < data.length; i++) {     _data[i] = {};     _data[i].label = data[i][this.fieldKey.text];     _data[i].value = data[i][this.fieldKey.value];    }    return _data; }}