正则截取两个字符串间的值

  let str="sdfsdf:12545.sdafs.dfsdf:98794564.sdfdf:";
        let getStr = str => {
            let reg = /:(.+?)\./g;
            let arr = str.match(reg);
            let newArr =[]
            for (let i =0;i<arr.length;i++) {
                newArr.push(arr[i].replace(/(:|\.)/g, ‘‘))
            }
            return newArr;
        }
        console.log(getStr(str)) // ["12545", "98794564"]

    let str="sdfsdf:12545.sdafs.dfsdf:98794564.sdfdf:";
        let getStr = str => {
            let reg = /:(.+?)\./g;
            let arr = str.match(reg);
            return arr.join(‘,‘).replace(/(:|\.)/g, ‘‘);
        }
        console.log(getStr(str))