<form action="1c.php" method="post" id="submit1">
<div class="row">
<div class="col-md-6">
<div class="card">
<div class="card-body">
<div class="form-group">
<table class="table">
<tr>
<th> Артикул</th><th> Наименование</th><th> Группа товара</th><th> Ед. измерения</th></tr>
<?For ($i=1; $i<5; $i++){?>
<tr>
<th><input type="text" name="[<?php echo $i; ?>][code]" value="" class="form-control" placeholder="Артикул"></th>
<th><input type="text" name="[<?php echo $i; ?>][name]" value="" class="form-control" placeholder="Наименование"></th>
<th><input type="text" name="[<?php echo $i; ?>][groups]" value="" class="form-control" placeholder="Группа товара"></th>
<th><input type="text" name="[<?php echo $i; ?>][unit]" value="" class="form-control" placeholder="Ед. измерения"></th></tr>
</div>
<? }?>
</div>
</table>
</div>
</div>
</div>
</div>
</div>
<div class="row">
<div class="col-md-6">
<div class="form-group">
<input class="form-control" type="hidden" name="date" value="2019-12-11">
<button type="submit" class="btn btn-google btn-lg btn-block" >Добавить</button>
</div>
</div>
</div>
</form>
<th><input type="text" name="code[<?php echo $i; ?>]" value="" class="form-control" placeholder="Артикул"></th>
<th><input type="text" name="name[<?php echo $i; ?>]" value="" class="form-control" placeholder="Наименование"></th>
<th><input type="text" name="groups[<?php echo $i; ?>]" value="" class="form-control" placeholder="Группа товара"></th>
<th><input type="text" name="unit[<?php echo $i; ?>]" value="" class="form-control" placeholder="Ед. измерения"></th></tr>
<th><input type="text" name="items[<?= $i; ?>][code]" value="" class="form-control" placeholder="Артикул"></th>
<th><input type="text" name="items[<?=$i; ?>][name]" value="" class="form-control" placeholder="Наименование"></th>
<th><input type="text" name="items[<?= $i; ?>][groups]" value="" class="form-control" placeholder="Группа товара"></th>
<th><input type="text" name="items[<?= $i; ?>][unit]" value="" class="form-control" placeholder="Ед. измерения"></th>