第五章表单

前端开发作者： 2024-08-25 19:45:02

表单是最重要也是最复杂的表单可能是WEB世界里最重要的,通过表单获取用户的输入.另一方面,表单看起来又是简单的,你放置一个input标签,一个submit按钮,然后点击按钮,提交,有什么难的呢? 实践证明,表单确实是很复杂的,理由如下: 表单输入意味着修改服务器与客户端的数据. 改变通常会需

Controls

// create a new Control with the value "Nate"
let nameControl = new Control("Nate");

let name = nameControl.value; // -> Nate

// now we can query this control for certain values:
nameControl.errors // -> StringMap<string,any> of errors
nameControl.dirty // -> false
nameControl.valid // -> true
// etc.

<!-- part of some bigger form -->
<input type="text" ngControl="name" />

let personInfo = new ControlGroup({
 firstName: new Control("Nate"),lastName: new Control("Murray"),zip: new Control("90210")
 })

personInfo.value; // -> {
 // firstName: "Nate",
 // lastName: "Murray",
 // zip: "90210"
 //}

 // now we can query this control group for certain values,which have sensible
 // values depending on the children Control's values:
 personInfo.errors // -> StringMap<string,any> of errors
 personInfo.dirty // -> false
 personInfo.valid // -> true
 // etc.

import { Component } from '@angular/core';
import { FORM_DIRECTIVES } from '@angular/common';
@Component({
  selector: 'demo-form-sku',directives: [FORM_DIRECTIVES],

<div class="ui raised segment">
    <h2 class="ui header">Demo Form: Sku</h2>
    <form #f="ngForm" (ngSubmit)="onSubmit(f.value)" class="ui form">
      <div class="field">
        Forms in Angular 2 127
        <label for="skuInput">SKU</label>
        <input type="text" id="skuInput" placeholder="SKU" ngControl="sku">
        <button type="submit" class="ui button">Submit</button>
      </div>
    </form>
  </div>

form 和 NgForm

<form #f="ngForm" (ngSubmit)="onSubmit(f.value)" class="ui form">
</form>

input和ngControl

<form #f="ngForm" (ngSubmit)="onSubmit(f.value)" class="ui form">
      <div class="field">
        Forms in Angular 2 127
        <label for="skuInput">SKU</label>
        <input type="text" id="skuInput" placeholder="SKU" ngControl="sku">
        <button type="submit" class="ui button">Submit</button>
      </div>
    </form>

export class DemoFormSku { onSubmit(form: any): void {
    console.log('you submitted value:',form);
  }
}

import { Component } from '@angular/core';
import { FORM_DIRECTIVES } from '@angular/common';

@Component({
  selector: 'demo-form-sku',template: `
  <div class="ui raised segment">
    <h2 class="ui header">Demo Form: Sku</h2>
    <form #f="ngForm"
          (ngSubmit)="onSubmit(f.value)"
          class="ui form">

      <div class="field">
        <label for="skuInput">SKU</label>
        <input type="text"
               id="skuInput"
               placeholder="SKU"
               ngControl="sku">
      </div>

      <button type="submit" class="ui button">Submit</button>
    </form>
  </div>
  `
})
export class DemoFormSku {
  onSubmit(form: any): void {
    console.log('you submitted value:',form);
  }
}

怎样使用FormBuilder

export class DemoFormSkuBuilder { myForm: ControlGroup;
  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
    'sku': ['ABC123'] });
}
onSubmit(value: string): void { 
    console.log('you submitted value: ',value);
}

在view中使用myForm

 <form [ngFormModel]="myForm"
          (ngSubmit)="onSubmit(myForm.value)"

<input
type="text"
id="skuInput"
placeholder="SKU"
[ngFormControl]="myForm.controls['sku']">

试试

import { Component } from '@angular/core';
import {
  FORM_DIRECTIVES,FormBuilder,ControlGroup
} from '@angular/common';

@Component({
  selector: 'demo-form-sku-builder',template: `
  <div class="ui raised segment">
    <h2 class="ui header">Demo Form: Sku with Builder</h2>
    <form [ngFormModel]="myForm" 
          (ngSubmit)="onSubmit(myForm.value)"
          class="ui form">

      <div class="field">
        <label for="skuInput">SKU</label>
        <input type="text" 
               id="skuInput" 
               placeholder="SKU"
               [ngFormControl]="myForm.controls['sku']">
      </div>

    <button type="submit" class="ui button">Submit</button>
    </form>
  </div>
  `
})
export class DemoFormSkuBuilder {
  myForm: ControlGroup;

  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku': ['ABC123']
    });
  }

  onSubmit(value: string): void {
    console.log('you submitted value: ',value);
  }
}

let control = new Control('sku',Validators.required);

constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku':  ['',Validators.required]

显示的将Control变量设置为实例变量

export class DemoFormWithValidationsExplicit {
  myForm: ControlGroup;
  sku: AbstractControl;

  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku':  ['',Validators.required]
    });

    this.sku = this.myForm.controls['sku'];
  }

  onSubmit(value: string): void {
    console.log('you submitted value: ',value);
  }
}

表单信息

<div *ngIf="!myForm.valid"

字段信息

[ngFormControl]="sku">
         <div *ngIf="!sku.valid"

字段色彩

<div class="field"
          [class.error]="!sku.valid && sku.touched">

指定特定的校验器

class="ui error message">SKU is invalid</div> 
<div *ngIf="sku.hasError('required')"

所有代码

/* tslint:disable:no-string-literal */
import { Component } from '@angular/core';
import {
  CORE_DIRECTIVES,FORM_DIRECTIVES,ControlGroup,Validators,AbstractControl
} from '@angular/common';

@Component({
  selector: 'demo-form-with-validations-explicit',directives: [CORE_DIRECTIVES,FORM_DIRECTIVES],template: `
  <div class="ui raised segment">
    <h2 class="ui header">Demo Form: with validations (explicit)</h2>
    <form [ngFormModel]="myForm"
          (ngSubmit)="onSubmit(myForm.value)"
          class="ui form">

      <div class="field"
          [class.error]="!sku.valid && sku.touched">
        <label for="skuInput">SKU</label>
        <input type="text"
               id="skuInput"
               placeholder="SKU"
               [ngFormControl]="sku">
         <div *ngIf="!sku.valid"
           class="ui error message">SKU is invalid</div>
         <div *ngIf="sku.hasError('required')"
           class="ui error message">SKU is required</div>
      </div>

      <div *ngIf="!myForm.valid"
        class="ui error message">Form is invalid</div>

      <button type="submit" class="ui button">Submit</button>
    </form>
  </div>
  `
})
export class DemoFormWithValidationsExplicit {
  myForm: ControlGroup;
  sku: AbstractControl;

  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku':  ['',Validators.required]
    });

    this.sku = this.myForm.controls['sku'];
  }

  onSubmit(value: string): void {
    console.log('you submitted value: ',value);
  }
}

export class DemoFormWithValidationsShorthand { 
    myForm: ControlGroup;
      constructor(fb: FormBuilder) {
            this.myForm = fb.group({
                'sku': ['',Validators.required] });
      }
      onSubmit(value: any): void {
        console.log('you submitted value:',value.sku);
      }
}

声明1个本地sku援用

myForm.find

<div class="field"
      [class.error]="!myForm.find('sku').valid && myForm.find('sku').touched">

通过NgFormControl导出

<input
type="text"
id="skuInput"
placeholder="SKU"
#sku="ngForm"
[ngFormControl]="myForm.controls['sku']">

<div *ngIf="!sku.control.valid"
class="ui error message">SKU is invalid</div>
<div *ngIf="sku.control.hasError('required')" class="ui error message">SKU is required</div>

sku变量的范围

// this won't work
   <div class="field"
[class.error]="!sku.control.valid && sku.control.touched">

全部代码

import { Component } from '@angular/core';
import {
  CORE_DIRECTIVES,Validators
} from '@angular/common';

@Component({
  selector: 'demo-form-with-validations-shorthand',template: `
<div class="ui raised segment">
  <h2 class="ui header">Demo Form: with validations (shorthand)</h2>
  <form [ngFormModel]="myForm"
        (ngSubmit)="onSubmit(myForm.value)"
        class="ui form">

    <div class="field"
      [class.error]="!myForm.find('sku').valid && myForm.find('sku').touched">
      <label for="skuInput">SKU</label>
      <input type="text"
             id="skuInput"
             placeholder="SKU"
             #sku="ngForm"
             [ngFormControl]="myForm.controls['sku']">
       <div *ngIf="!sku.control.valid"
         class="ui error message">SKU is invalid</div>
       <div *ngIf="sku.control.hasError('required')"
         class="ui error message">SKU is required</div>
    </div>

    <div *ngIf="!myForm.valid"
      class="ui error message">Form is invalid</div>

    <button type="submit" class="ui button">Submit</button>
  </form>
</div>
  `
})
export class DemoFormWithValidationsShorthand {
  myForm: ControlGroup;

  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku':  ['',Validators.required]
    });
  }

  onSubmit(value: any): void {
    console.log('you submitted value:',value.sku);
  }
}

export class Validators {
  static required(c: Control): StringMap<string,boolean> {
    return isBlank(c.value) || c.value == "" ? {"required": true} : null;
}

编写1个校验器

function skuValidator(control: Control): { [s: string]: boolean } { if (!control.value.match(/^123/)) {
    return {invalidSku: true};
  }
}

分配校验器给Control

this.myForm = fb.group({
      'sku':  ['',Validators.compose([
        Validators.required,skuValidator])]
    });

<div *ngIf="sku.hasError('invalidSku')"
class="ui error message">SKU must begin with <tt>123</tt></div>

export class DemoFormWithEvents {
  myForm: ControlGroup;
  sku: AbstractControl;

  constructor(fb: FormBuilder) {
    this.myForm = fb.group({
      'sku':  ['',Validators.required]
    });

    this.sku = this.myForm.controls['sku'];

    this.sku.valueChanges.subscribe(
      (value: string) => {
        console.log('sku changed to:',value);
      }
    );

    this.myForm.valueChanges.subscribe(
      (form: any) => {
        console.log('form changed to:',form);
      }
    );

  }

  onSubmit(form: any): void {
    console.log('you submitted value:',form.sku);
  }
}

export class DemoFormNgModel { 
    myForm: ControlGroup; productName: string;
    constructor(fb: FormBuilder) {
        this.myForm = fb.group({
        'productName': ['',Validators.required] });
    }
    onSubmit(value: string): void { 
        console.log('you submitted value: ',value);
    }
}

<input
    type="text"
    id="productNameInput"
    placeholder="Product Name"
    [ngFormControl]="myForm.find('productName')"
    [(ngModel)]="productName">

<div class="ui info message">
The product name is: {{productName}}
</div>

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第五章表单

Controls

form 和 NgForm

input和ngControl

怎样使用FormBuilder

在view中使用myForm

试试

显示的将Control变量设置为实例变量

表单信息

字段信息

字段色彩

指定特定的校验器

所有代码

声明1个本地sku援用

myForm.find

通过NgFormControl导出

sku变量的范围

全部代码

编写1个校验器

分配校验器给Control

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相关新闻

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热门标签

第五章 表单

Controls

form 和 NgForm

input和ngControl

怎样使用FormBuilder

在view中使用myForm

试试

显示的将Control变量设置为实例变量

表单信息

字段信息

字段色彩

指定特定的校验器

所有代码

声明1个本地sku援用

myForm.find

通过NgFormControl导出

sku变量的范围

全部代码

编写1个校验器

分配校验器给Control

猜你喜欢

相关新闻

推荐模板

推荐精华

热门标签

第五章表单