我刚来拉拉维尔。如何查找是否存在记录?
$user = User::where('email', '=', Input::get('email'));
我能做什么来查看$user是否有记录?
我刚来拉拉维尔。如何查找是否存在记录?
$user = User::where('email', '=', Input::get('email'));
我能做什么来查看$user是否有记录?
当前回答
Laravel 6或顶部:写表名,然后给出where子句条件,例如where('id', $request->id)
public function store(Request $request)
{
$target = DB:: table('categories')
->where('title', $request->name)
->get()->first();
if ($target === null) { // do what ever you need to do
$cat = new Category();
$cat->title = $request->input('name');
$cat->parent_id = $request->input('parent_id');
$cat->user_id=auth()->user()->id;
$cat->save();
return redirect(route('cats.app'))->with('success', 'App created successfully.');
}else{ // match found
return redirect(route('cats.app'))->with('error', 'App already exists.');
}
}
其他回答
最短工作选项:
// if you need to do something with the user
if ($user = User::whereEmail(Input::get('email'))->first()) {
// ...
}
// otherwise
$userExists = User::whereEmail(Input::get('email'))->exists();
如果你想插入一个唯一的记录,你可以使用laravel验证:
$validated = $request->validate([
'title' => 'required|unique:usersTable,emailAddress|max:255',
]);
但是你也可以用这些方法:
1:
if (User::where('email', $request->email)->exists())
{
// object exists
} else {
// object not found
}
2:
$user = User::where('email', $request->email)->first();
if ($user)
{
// object exists
} else {
// object not found
}
3:
$user = User::where('email', $request->email)->first();
if ($user->isNotEmpty())
{
// object exists
} else {
// object not found
}
4:
$user = User::where('email', $request->email)->firstOrCreate([
'email' => 'email'
],$request->all());
最好的解决方案之一是使用firstOrNew或firstOrCreate方法。文档中有更多关于这两者的详细信息。
你已经看到了很多解决方案,但是神奇的检查语法可以是这样的,
$model = App\Flight::findOrFail(1);
$model = App\Flight::where('legs', '>', 100)->firstOrFail();
当没有找到任何相关模型时,它会自动引发一个响应404的异常,有时你可能希望在没有找到模型时抛出一个异常。这在路由或控制器中特别有用。fingernail和firstOrFail方法将检索查询的第一个结果;但是,如果没有找到结果,则会抛出一个Illuminate\Database\Eloquent\ModelNotFoundException异常。
裁判:https://laravel.com/docs/5.8/eloquent # retrieving-single-models
这将检查用户表中是否存在所请求的电子邮件:
if (User::where('email', $request->email)->exists()) {
//email exists in user table
}