將字符串按照空格進(jìn)行拆分，對每一段進(jìn)行校驗(yàn)即可，只要其中一個不滿足，那么整段字符串就不滿足要求
functionhasLetterAndNum(str){
returnstr.split(/\s+/).every(item=>/^(?=.*?[0-9])(?=.*?[a-z])[0-9a-z]+$/.test(item))
}
測試：
hasLetterAndNum('qwerty')//false
hasLetterAndNum('123456')//false
hasLetterAndNum('qwe123')//true
hasLetterAndNum('qwe123qweabc46')//false
hasLetterAndNum('qwe1235566abc46')//false
hasLetterAndNum('qwe1235566cabc46')//true
hasLetterAndNum('qwe1235566cabc46')//true