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##Please verify that it is not empty and verify it It must be numbers, letters, underscores, and the beginning, forming 6 to 10 digits. Can my js part be written like this? Or I should first determine whether it is empty, and then verify the matching characters. Let’s write it like this together, right? I am self-taught. If there is something wrong with the above code, please help me. Please help me. Thanks.
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
You should start the detection according to the first step with user input and then verify step by step