<div class="btnlog" onclick="
			var name = document.getElementById('name');
			var us = document.getElementById('user');
			var mk = document.getElementById('mkhau');
			var rmk = document.getElementById('rkhau');
			var sl = document.getElementById('slink');
			var kt = true;
			<?php
				$connect = mysqli_connect("localhost","root","","lsonline");
				mysqli_query($connect,"SET NAMES 'utf8'");
				$query = "SELECT * FROM user";
				$data = mysqli_query($connect,$query);
				while ($dong = mysqli_fetch_array($data)) {
				?>
					if (us.value == <?php echo $dong['user'] ?>){
						kt = false;
						<?php break; ?>//câu lệnh này không hoạt động
					}
				<?php
				}
			?>">
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