Toast抽取，创建一个Utils

import promptAction from '@ohos.promptAction';
import display from '@ohos.display';
export function ToastUtils(msg:string){try {promptAction.showToast({message: msg,duration: 1500,bottom:450});} catch (error) {console.error(`showToast args error code is ${error.code}, message is ${error.message}`);};
}

  使用：

import promptAction from '@ohos.promptAction';
import { StringIsEmpty } from '../utils/StringUtils';
import { ToastUtils } from '../utils/ToastUtils';
@Entry
@Component
struct SubmitFormPage {@State message: string = 'Hello World'@State inputText: string = ""build() {Row() {Column({space:10}) {TextInput({ text: this.inputText, placeholder: '请输入名字' }).fontSize(15).fontWeight(FontWeight.Normal).width('100%').height(50).backgroundColor('#f6f6f6').borderRadius(10).onChange((value) => {this.inputText= value})Button("提交").height(50).width(100).backgroundColor(Color.Blue).alignSelf(ItemAlign.Center).onClick(()=>{let isEmpty = StringIsEmpty(this.inputText);if (isEmpty) {ToastUtils("请输入文字~")}else{ToastUtils(this.inputText)}})}.width('100%').justifyContent(FlexAlign.Center).alignItems(HorizontalAlign.Start)}.height('100%')}
}

stringUtils只是判断是否为空

export function StringIsEmpty(str:string){return str === null || str === undefined || str.trim().length === 0;
}