字符串文字中的 TypeScript 空行答案

【问题标题】：TypeScript empty row in string literal字符串文字中的 TypeScript 空行
【发布时间】：2022-11-22 19:43:18
【问题描述】：

我想创建一个带有可选值 numberOfResidents 的字符串文字。

function mapBuildingToComment(building: Building) {
    return `
    ### Building information ###
    Street: ${building.address.street}
    HouseNumber: ${building.address.houseNumber}
    ${mapNumberOfResidents(building.numberOfResidents)}
    City: ${building.address.city}
    `
}

function mapNumberOfResidents(numberOfResidents?: string) {
    if (!numberOfResidents) return ''

    return `Number of residents: ${numberOfResidents}`
}

我现在的问题是，当 numberOfResidents 未定义时，我的输出中有一个空行。

Output:
    ### Building information ###
    Street: Teststreet
    HouseNumber: 1

    City: Test

我怎样才能做到没有空行并且城市在门牌号正下方？

【问题讨论】：

标签： typescript string string-literals

【解决方案1】：

删除换行符并仅在需要时添加它

function mapBuildingToComment(building: typeof b) {
    return `
    ### Building information ###
    Street: ${building.address.street}
    HouseNumber: ${building.address.houseNumber}
${building.numberOfResidents ? '
    ' + mapNumberOfResidents(building.numberOfResidents) : ''}
    City: ${building.address.city}
    `
}

function mapNumberOfResidents(numberOfResidents?: string) {
    if (!numberOfResidents) return ''

    return `Number of residents: ${numberOfResidents}`
}

const b = {address: {street: '123', houseNumber: 245, city: 'asd'}, numberOfResidents: '3'}
console.log(mapBuildingToComment(b))
b.numberOfResidents = ''
console.log(mapBuildingToComment(b))

另一种选择是使用 s.replaceAll(/ s+(?= )/g, '') 从结果中删除空行

【讨论】：