Why does thinkphp5 always report an error when uploading multiple files using the multiple attribute?

Why does thinkphp5 always report errors when uploading multiple files using the multiple attribute?

error message:

HTML Code:

<input name="file" type="file" multiple/> 
<input type="submit" value="" class="btn btn-primary">

php Code:

if($files = request()->file("file"))          
            foreach ($files as $file) 
            {         
            $info = $file->move(ROOT_PATH . "public" . DS ."static","");
            if($info){
                $path_parts = pathinfo(ROOT_PATH . "public" . DS . "static" ."\\". $info->getFilename());
                //
                $type=$path_parts["extension"];
                $name=$path_parts["filename"];
                $size=(filesize(ROOT_PATH . "public" . DS . "static" ."\\". $info->getFilename())>>10)."KB";
                $data=["name"=>$name,"type"=>$type,"size"=>$size];
                Db::table("doc")->insert($data);

                $this->success("");
            }else{
                //
                $this->error($file->getError());    
            }
            }

I am looking at the thinkphp5 manual, why does the move function always report an error?

Html php thinkphp5 file-upload

Mar.09,2021

The multiple files of

tp5 do not refer to this < input name= "file" type= "file" multiple/ >.
refers to
< input type= "file" name= "file []" / >

< input type= "file" name= "file []" / >

< input type= "file" name= "file []" / >

for an input, in addition to adding multiple attribute, name

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