Question

我正在尝试创建注册表。条件是，如果该人已经注册，则该人不能再注册。

我需要的

我有以下php MySQL查询，用于检查是否存在现有条目

  $duplicateCheckQuery = "SELECT * FROM registrationFormDetails WHERE email ='?' AND competition ='?'";
	$stmt = mysqli_stmt_init($conn);
	if(!mysqli_stmt_prepare($stmt, $duplicateCheckQuery)){
		echo "Duplicate check SQL statement failed";
	}else{
		mysqli_stmt_bind_param($stmt,"ss", $email, $competition);
		mysqli_stmt_execute($stmt);
		$result = mysqli_stmt_get_result($stmt);
		$resultCheck = mysqli_num_rows($result);

		if($resultCheck>0){
			
			echo '<script>
			$("#exampleModal").modal("show")
			
			</script>';
         }else{
             //register
        }
      }

我从Bootstrap网站复制了以下模式代码

<!-- Modal -->
<div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalLabel">Modal title</h5>
        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
          <span aria-hidden="true">&times;</span>
        </button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

提交表单时，我希望出现模式。但是它没有显示，而是似乎已提交表单。有人知道我在哪里错吗？

Answer 1

模态在窗口完全加载之前被初始化，这就是为什么它不起作用的原因。因此您可以将代码更改为此代码，它可以完美运行

echo '<script>
        $(document).ready(function(){
            $("#exampleModal").modal("show")
        });
        </script>';

Answer 2

正确答案如下。实际上，初始代码可以通过删除？周围的'标记来起作用。在准备好的语句中标记。您也可以将脚本放在document.ready

中

  $duplicateCheckQuery = "SELECT * FROM registrationFormDetails WHERE email =? AND competition =?";
	$stmt = mysqli_stmt_init($conn);
	if(!mysqli_stmt_prepare($stmt, $duplicateCheckQuery)){
		echo "Duplicate check SQL statement failed";
	}else{
		mysqli_stmt_bind_param($stmt,"ss", $email, $competition);
		mysqli_stmt_execute($stmt);
		$result = mysqli_stmt_get_result($stmt);
		$resultCheck = mysqli_num_rows($result);

		if($resultCheck>0){
			
			echo '<script>
			$("#exampleModal").modal("show")
			
			</script>';
         }else{
             //register
        }
      }

然后给出模态代码

<!-- Modal -->
<div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalLabel">Modal title</h5>
        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
          <span aria-hidden="true">&times;</span>
        </button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

数据库检查后未显示模态

2 个答案: