Check record if exist (instantly) in MVC - sql

Question

I want to check instantly, after i type something in text box, if a record exist in my database. I managed to return on my page number of how many times record exist in database, but i want to return a message (if exists or not).
So, the question is: How can I display a message if record exist or not?
PS. I`m using ASP.NET MVC
Here is my code:
Model class:
public class AdminModel
{
[Remote("IsUniq", "Home", HttpMethod = "POST")]
public string FirstName { get; set; }
}
My controller action(HomeController):
[HttpPost]
public JsonResult IsUniq(string FirstName)
{
IPAdressProgramEntities r = new IPAdressProgramEntities();
var user = r.spLineExist(FirstName);//spLineExist - procedure in SQL- return how many time record exist in database
return Json(user); //return on my page how many times record exists
}
And this is my view:
#using (Html.BeginForm())
{
<div class="editor-field">
#Html.EditorFor(model => model.FirstName)
#Html.ValidationMessageFor(model => model.FirstName)
</div>
}
PS WebConfig is configured and also scripts are included in my view.
Thank you.

Answer 1

If you simply want to show message when your count is greater than 0, Add an Error message property to your data annotation.
[Remote("IsUniq", "Home", HttpMethod = "POST", ErrorMessage = "Exist")]
public string FirstName { get; set; }
and return true of false from your action method. To show the error message, you need to return false from the method.
var responseToSend = user!=0; //user is the count returned by your existing code
return Json(responseToSend);
If you want to show both the messages (Exists/ Not exists), you may consider handling the check yourself with a little jQuery ajax call than relying on the remote data annotation. So simply remove the data annotation.
And listen to the keyup event on this input field, read the value, send to server to check it exist or not, based on the result, show appropriate message
$(function () {
$("#FirstName")
.keyup(function () {
$.post('/Home/IsUniq?FirstName=' + $(this).val(), function (res) {
if (res) {
$("span[data-valmsg-for='FirstName']").text("Not Available")
} else {
$("span[data-valmsg-for='FirstName']").text("Available")
}
})
});
});
Make sure you return True or False from your action method.
[HttpPost]
public JsonResult IsUniq(string FirstName)
{
//If exists
return Json(true);
else
return Json(false);
}