简单表单校验

傻瓜式校验

直接复制Antd中demo

<form nz-form [nzLayout]="'inline'" [formGroup]="validateForm" (ngSubmit)="submitForm()"> <nz-form-item> <nz-form-control nzErrorTip="Please input your username!"> <nz-input-group nzPrefixIcon="user"> <input formControlName="userName" nz-input placeholder="Username" /> </nz-input-group> </nz-form-control> </nz-form-item> <nz-form-item> <nz-form-control nzErrorTip="Please input your Password!"> <nz-input-group nzPrefixIcon="lock"> <input formControlName="password" nz-input type="password" placeholder="Password" /> </nz-input-group> </nz-form-control> </nz-form-item> <nz-form-item> <nz-form-control> <button nz-button nzType="primary" [disabled]="!validateForm.valid">Log in</button> </nz-form-control> </nz-form-item></form>validateForm!: FormGroup; submitForm(): void { for (const i in this.validateForm.controls) { this.validateForm.controls[i].markAsDirty(); this.validateForm.controls[i].updateValueAndValidity(); } } constructor(private fb: FormBuilder) {} ngOnInit(): void { this.validateForm = this.fb.group({ userName: [null, [Validators.required]], password: [null, [Validators.required]], remember: [true] }); }

此类表单校验较为单一，或者要求比较低，通常即为required校验，错误信息提示也多为固定不变。

智能化校验

表单一旦开始有具体的细节校验或者复杂的业务参杂，校验提示必须准确、清晰。
userName为例，除了为必填项，必然需要符合某种格式，亦或是指定邮箱格式等，那么校验必须同时反映出错误类型，本例假设用户名有长度要求进行演示。

<nz-form-control [nzErrorTip]="getErrTipByField('userName')"> <nz-input-group nzPrefixIcon="user"> <input formControlName="userName" nz-input placeholder="Username" /> </nz-input-group> </nz-form-control>export class SimpleFormComponent implements OnInit { validateForm: FormGroup; errMessageMap = {}; constructor( private fb: FormBuilder ) { } ngOnInit() { this.errMessageMap = { userName: { required: 'please input your name!', minlength: 'please input at least least 5 character' }, password: { required: 'please input your password!' } }; this.validateForm = this.fb.group({ userName: [null, [Validators.required, Validators.minLength(5)]], password: [null, [Validators.required]], remember: [true] }, { updateOn: 'change' }); } submitForm(): void { if (this.validateForm.controls) { for (const i in this.validateForm.controls) { if (this.validateForm.controls[i]) { this.validateForm.controls[i].markAsDirty(); this.validateForm.controls[i].updateValueAndValidity(); } } } } getErrTipByField(fieldName) { const errors = this.validateForm.get(fieldName).errors; let errMsg = ''; for (const key in errors) { if (errors.hasOwnProperty(key)) { errMsg += this.errMessageMap[fieldName][key]; } } return errMsg; }}

构建出一个数据对象，以满足不同字段下不同错误类型的错误提示，根据业务需求，决定是否显示全部错误信息或者按照业务优先级显示。

其它细节

表单校验时机可以设置，默认为change,可选blur 、submit

表单验证正确的，想要提示勾号可以添加属性 nzHasFeedback

submit中那段代码是重新对表单进行验证了，一般验证中是不需要的，动态表单验证后续结合自定义表单服务进行演示。

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