JS rgb与十六进制间的转换

rgb转十六进制

const rgbToString = (str) => {
    let result = ''
    if (str.indexOf("#") === 0) {
        result = str
    } else if (str.indexOf("rgb(") === 0) {
        const colors = str.replace(/rgb\(/g, "").replace(/\)/g, "").split(",")
        const r = parseInt(colors[0]).toString(16).length === 1 ? "0" + parseInt(colors[0]).toString(16) : parseInt(colors[0]).toString(16)
        const g = parseInt(colors[1]).toString(16).length === 1 ? "0" + parseInt(colors[1]).toString(16) : parseInt(colors[1]).toString(16)
        const b = parseInt(colors[2]).toString(16).length === 1 ? "0" + parseInt(colors[2]).toString(16) : parseInt(colors[2]).toString(16)
        result = `#${r}${g}${b}`
    }
    return result
}

运行结果

十六进制转rgb

const stringToRgb = (str, mode = "string") => {
    const template = str.toLowerCase()
    let result = ''
    if (template.indexOf("rgb(") === 0) {
        result = template
    } else if (template.indexOf("rgba(") === 0) {
        const colors = template.replace(/rgba\(/g, "").replace(/\)/g, "").split(",")
        const r = colors[0]
        const g = colors[1]
        const b = colors[2]
        result = `rgb(${r},${g},${b})`
    } else if (template.indexOf("#") === 0) {
        let colors = template.replace(/#/g, "")
        let resultArr = []
        if (colors.length === 3) {
            colors = colors.replace(/[0-9a-f]/g, (str) => {
                return str + str
            })
        }
        for (let i = 0; i < colors.length; i += 2) {
            resultArr.push(parseInt(colors[i] + colors[i + 1], 16))
        }
        result = `rgb(${resultArr.join(",")})`
    }
    if (mode === "string") {
        return result
    } else if (mode === "array") {
        return result.replace(/rgb\(/g, "").replace(/\)/g, "").split(",")
    }
}

运行结果