临时文档

@Entry
@Component
struct Jsq {
  @State display: string = '0'
  @State firstOperand: string = ''
  @State operator: string = ''
  @State waitingForSecondOperand: boolean = false

  appendDigit(digit: string) {
    if (this.waitingForSecondOperand) {
      this.display = digit
      this.waitingForSecondOperand = false
    } else {
      this.display = this.display === '0' ? digit : this.display + digit
    }
  }

  appendDot() {
    if (this.waitingForSecondOperand) {
      this.display = '0.'
      this.waitingForSecondOperand = false
    } else if (!this.display.includes('.')) {
      this.display = this.display + '.'
    }
  }

  setOperator(nextOperator: string) {
    const inputValue = parseFloat(this.display)
    
    if (this.operator && this.waitingForSecondOperand) {
      this.operator = nextOperator
      return
    }
    
    if (this.firstOperand === '') {
      this.firstOperand = this.display
    } else if (this.operator) {
      const result = this.calculate(parseFloat(this.firstOperand), inputValue, this.operator)
      this.display = String(result)
      this.firstOperand = String(result)
    }
    
    this.waitingForSecondOperand = true
    this.operator = nextOperator
  }

  calculate(first: number, second: number, op: string): number {
    switch (op) {
      case '+': return first + second
      case '-': return first - second
      case '×': return first * second
      case '÷': return second !== 0 ? first / second : 0
      default: return second
    }
  }

  performEqual() {
    if (!this.operator || this.waitingForSecondOperand) return
    
    const secondOperand = parseFloat(this.display)
    let result = this.calculate(parseFloat(this.firstOperand), secondOperand, this.operator)
    
    if (result === 0 && this.operator === '÷') {
      this.display = 'Error'
    } else {
      this.display = String(result)
      if (!Number.isInteger(result)) {
        this.display = parseFloat(this.display).toFixed(8).replace(/\.?0+$/, '')
      }
    }
    
    this.firstOperand = ''
    this.operator = ''
    this.waitingForSecondOperand = false
  }

  clear() {
    this.display = '0'
    this.firstOperand = ''
    this.operator = ''
    this.waitingForSecondOperand = false
  }

  build() {
    Column({ space: 15 }) {
      Column({ space: 10 }) {
        Text(this.display)
          .fontSize(48)
          .fontWeight(FontWeight.Bold)
          .fontColor('#333')
          .width('92%')
          .textAlign(TextAlign.End)
          .maxLines(1)
      }
      .width('100%')
      .height('30%')
      .justifyContent(FlexAlign.End)
      .alignItems(HorizontalAlign.Center)
      .padding({ right: 20, bottom: 20 })

      Column({ space: 10 }) {
        Row({ space: 10 }) {
          Button('C')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ff6b6b')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.clear())
          Button('÷')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ffa502')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.setOperator('÷'))
          Button('×')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ffa502')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.setOperator('×'))
          Button('⌫')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ffa502')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => {
              if (this.display.length > 1) {
                this.display = this.display.slice(0, -1)
              } else {
                this.display = '0'
              }
            })
        }
        .width('100%')
        .height('15%')
        .justifyContent(FlexAlign.SpaceEvenly)

        Row({ space: 10 }) {
          Button('7')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('7'))
          Button('8')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('8'))
          Button('9')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('9'))
          Button('-')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ffa502')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.setOperator('-'))
        }
        .width('100%')
        .height('15%')
        .justifyContent(FlexAlign.SpaceEvenly)

        Row({ space: 10 }) {
          Button('4')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('4'))
          Button('5')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('5'))
          Button('6')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#333')
            .backgroundColor('#fff')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.appendDigit('6'))
          Button('+')
            .fontSize(28)
            .fontWeight(FontWeight.Medium)
            .fontColor('#fff')
            .backgroundColor('#ffa502')
            .width('23%')
            .height('100%')
            .borderRadius(12)
            .onClick(() => this.setOperator('+'))
        }
        .width('100%')
        .height('15%')
        .justifyContent(FlexAlign.SpaceEvenly)

        Row({ space: 10 }) {
          Column({ space: 10 }) {
            Row({ space: 10 }) {
              Button('1')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#333')
                .backgroundColor('#fff')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.appendDigit('1'))
              Button('2')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#333')
                .backgroundColor('#fff')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.appendDigit('2'))
              Button('3')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#333')
                .backgroundColor('#fff')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.appendDigit('3'))
            }
            .width('100%')
            .height('15%')
            .justifyContent(FlexAlign.SpaceEvenly)

            Row({ space: 10 }) {
              Button('0')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#333')
                .backgroundColor('#fff')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.appendDigit('0'))
              Button('.')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#333')
                .backgroundColor('#fff')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.appendDot())
              Button('=')
                .fontSize(28)
                .fontWeight(FontWeight.Medium)
                .fontColor('#fff')
                .backgroundColor('#1FA485')
                .width('32%')
                .height('100%')
                .borderRadius(12)
                .onClick(() => this.performEqual())
            }
            .width('100%')
            .height('15%')
            .justifyContent(FlexAlign.SpaceEvenly)
          }
          .width('73%')
        }
      }
      .width('100%')
      .height('70%')
      .padding({ left: 10, right: 10 })
    }
    .width('100%')
    .height('100%')
    .backgroundColor('#f5f5f5')
  }
}