先找到最后一个.的索引, 再使用字符串截取到最后

{"css":"","js":"function removeWithoutCopy(arr, item) {\n    let length = arr.length\n    while(length--){\n        if(arr[length]===item){\n            arr.splice(length,1)\n        }\n    }\n    return arr\n}","html":"","libs":[]}