Typescript_GetUrlSearchParams

function getQueryVariable(key: string): string {
    let reg = new RegExp(`(^|&)${key}=([^&]*)(&|$)`);
    let res = window.location.search.slice(1).match(reg);
    let ret = '';
    if (res != null) {
        ret = res[2];
    } 
    return decodeURIComponent(ret);
}