前端开发零碎知识记录

//1：trim()去除string前后空格； str.replace(/[ ]/g,””) 去除string空格

var a = ‘ abcd efg hijkl ‘

console.log(‘去前后空格’, a.trim())

console.log(‘去空格 ‘, a.replace(/[ ]/g, ”))

//2：数字转换成金额方式：

//链接：[js链接](https://www.cnblogs.com/mingmingruyuedlut/archive/2013/05/19/3082177.html)

var num = 123456.2346

num.toLocaleString() //123,456.235

console.log(num.toLocaleString())

//方法：用prototype方式将number数值转化为货币格式

Number.prototype.formatMoney = function(places, symbol, thousand, decimal) {

    places = !isNaN((places = Math.abs(places))) ? places : 2

    symbol = symbol !== undefined ? symbol : ‘$’

    thousand = thousand || ‘,’

    decimal = decimal || ‘.’

    var number = this,

        negative = number < 0 ? ‘-‘ : ”,

        i =

            parseInt((number = Math.abs(+number || 0).toFixed(places)), 10) +

            ”,

        j = (j = i.length) > 3 ? j % 3 : 0

    return (

        symbol +

        negative +

        (j ? i.substr(0, j) + thousand : ”) +

        i.substr(j).replace(/(\d{3})(?=\d)/g, ‘$1’ + thousand) +

        (places

            ? decimal +

             Math.abs(number – i)

                    .toFixed(places)

                    .slice(2)

            : ”)

    )

}

//例

var revenue = 12345678.1569

console.log(revenue.formatMoney()) // $12,345,678.00

console.log(revenue.formatMoney(0, ‘HK ‘)) // HK$ 12,345,678

//货币字符串的格式转化为number类型

var price = revenue.formatMoney(4, ‘HK$ ‘)

parseFloat(price.replace(/[^0-9-.]/g, ”)) // 12345.99

console.log(parseFloat(price.replace(/[^0-9-.]/g, ”)))

//方法：用function 函数方法将number数值转化为货币格式

function formatMoney(number, places, symbol, thousand, decimal) {

    number = number || 0

    places = !isNaN((places = Math.abs(places))) ? places : 2

    symbol = symbol !== undefined ? symbol : ‘$’

    thousand = thousand || ‘,’

    decimal = decimal || ‘.’

    var negative = number < 0 ? ‘-‘ : ”,

        i =

            parseInt((number = Math.abs(+number || 0).toFixed(places)), 10) +

            ”,

        j = (j = i.length) > 3 ? j % 3 : 0

    return (

        symbol +

        negative +

        (j ? i.substr(0, j) + thousand : ”) +

        i.substr(j).replace(/(\d{3})(?=\d)/g, ‘$1’ + thousand) +

        (places

            ? decimal +

             Math.abs(number – i)

                    .toFixed(places)

                    .slice(2)

            : ”)

    )

}

//例

console.log(formatMoney(12345, 2, ‘hk’)) // hk12,345.00

//例如路径 blueberry.uat.byinfo.tech:70/console/html/login.html

console.log(window.location.protocol) //http:即，协议

console.log(window.location.host) //blueberry.uat.byinfo.tech:70设置或取得当前 URL 的主机名称和端口号;如果端口是默认的 80 端口而被省略，那么该属性取得的数据就不包含端口号 console.log(window.location.hostname);//即，设置或取得当前 URL 的主机名

console.log(window.location.hostname) //blueberry.uat.byinfo.tech设置或取得当前 URL 的主机名

console.log(window.location.protocol + ‘//’ + window.location.host)