/**
 *  dataURL 转换到 Blob
 */
export function dataURLtoBlob(dataURL: string) {
    let byteString: string
    if (dataURL.split(",")[0].indexOf("base64") >= 0) byteString = atob(dataURL.split(",")[1])
    else byteString = unescape(dataURL.split(",")[1])

    let mimeString = dataURL.split(",")[0].split(":")[1].split(";")[0]

    let ia = new Uint8Array(byteString.length)
    for (let i = 0; i < byteString.length; i++) {
        ia[i] = byteString.charCodeAt(i)
    }

    return new Blob([ia], {
        type: mimeString,
    })
}