wxappb2b/GuangZuan/miniprogram/components/input-number/index.ts

// 赶进度待优化
Component({
    properties: {
        value: {
            type: null,
            value: 0,
            observer() {
                this.updated()
            }
        },
        //最小数值
        min: {
            type: Number,
            value: -999999
        },
        //最大数值
        max: {
            type: Number,
            value: 999999,
            observer() {
                this.updated()
            }
        },
        //递增或递减步长
        step: {
            type: Number,
            value: 1
        },
        //是否禁用
        disabled: {
            type: Boolean,
            value: false
        },
        //是否禁用输入
        disabledInput: {
            type: Boolean,
            value: false
        },
        //是否整数
        integer: {
            type: Boolean,
            value: false
        }
    },
    data: {
        disabledMinus: false,
        disabledAdd: false
    },
    methods: {
        //数据更新
        updated() {
            const val = this.data.value
            if (val == '' || isNaN(val)) return

            if (val <= this.data.min) {
                this.setData({
                    disabledMinus: true,
                    value: this.data.min
                })
            } else {
                this.setData({
                    disabledMinus: false
                })
            }

            if (val >= this.data.max) {
                this.setData({
                    disabledAdd: true,
                    value: this.data.max
                })
            } else {
                this.setData({
                    disabledAdd: false
                })
            }
        },
        //实时监听input输入
        inputChange(e: WechatMiniprogram.Input) {
            this.setData({
                value: e.detail.value
            })
        },
        //计算精度
        fixedFloat(a: number, b: number, sign: string) {
            const handle = (x: number): [string, number] => {
                let y = String(x)
                let p = y.lastIndexOf('.')
                if (p === -1) {
                    return [y, 0]
                } else {
                    return [y.replace('.', ''), y.length - p - 1]
                }
            }
            // v 操作数1, w 操作数2, s 操作符, t 精度
            const operate = (v: number, w: number, s: string, t: number) => {
                switch (s) {
                    case '+':
                        return (v + w) / t
                    case '-':
                        return (v - w) / t
                    case '*':
                        return (v * w) / (t * t)
                    case '/':
                        return (v / w)
                    default:
                        return 0
                }
            }

            const padding0 = (p: number) => {
                var z = ''
                while (p--) {
                    z += '0'
                }
                return z
            }

            const c: [string, number] = handle(a)
            const d: [string, number] = handle(b)
            let k = 0

            if (c[1] === 0 && d[1] === 0) {
                return operate(+c[0], +d[0], sign, 1)
            } else {
                k = Math.pow(10, Math.max(c[1], d[1]))
                if (c[1] !== d[1]) {
                    if (c[1] > d[1]) {
                        d[0] += padding0(c[1] - d[1])
                    } else {
                        c[0] += padding0(d[1] - c[1])
                    }
                }
                return operate(+c[0], +d[0], sign, k)
            }
        },
        minus() {
            this.setData({
                value: this.fixedFloat(this.data.value, this.data.step, '-')
            }, () => {
                this.triggerEvent('change', this.data.value)
            })
        },
        add() {
            this.setData({
                value: this.fixedFloat(this.data.value, this.data.step, '+')
            }, () => {
                this.triggerEvent('change', this.data.value)
            })
        },
        //失去焦点
        inputBlur() {
            if (this.data.value === '' || isNaN(this.data.value)) {
                if (this.data.min > 0) {
                    this.setData({
                        value: this.data.min
                    })
                } else {
                    this.setData({
                        value: this.data.max < 0 ? this.data.max : 0
                    })
                }
            } else {
                if (this.data.integer) {
                    this.setData({
                        value: parseInt(this.data.value)
                    })
                }
            }
            this.triggerEvent('change', this.data.value)
        }
    }
})