Javascript - Check Email Id Already Exists In Database When Losing Focus
Mar 18, 2011
I want to check the entered email id already exists in my database or not. For that I need the Text box lost focus event so that I can call it in update panel trigger asynchronously. whereas in my event I can check whether the entered value exists in database or not.
I want to validate the email id in clients side, so that to prevent the postback of page to server, and every user should registered with email id... so i want to validate email id at client side.. i.e. should be check it is exist in the database or not.
In addition to the process of regex syntax validation of Email Addresses entered by users, I'm trying to check if the entered email address is a real one and does exist?The best I could achieve is to "Ping" the host the email address is associated with. But there are some other terms in the industry like Handshaking with Email Server, etc.not necessarily with 100% confirmation accurary!
How can I check if an email address actually exists?
I have a list of email addresses which I want to screen for dead email accounts (without sending an email msg with a hyperlink). Is there a web-service for this? Or C# code (which I prever instead of sending the data to someone else)?
In the new user registration page, how to check whether the email id entered by a user is valid? I want to check the entered email id actually exists before the user submits his information. do not give code for checking email id string using regular expression, I want to check whether the entered email id actually exists.
I'm trying to performa an ajax validation for e-mail address. I need to know if user is already registered so I need to check it in my database. There is similar example:
Suppose I have a master page where I have written some javascript to access the value of a particular asp.net text box, which resides in one of its content pages, but not in all the pages. This piece of javascript code can't be moved to that particular content page because of some restrictions.
Now I need a way to determine whether or not that text box exists in the page, which will imply that the content page containing that text box has been loaded.
I have a SQL database that creates a record for every document uploaded by the user to the server. I want to check this table before a user uploads a document to ensure they don't upload a file with name that already exists.
I know how to make the connection and make the SqlCommand to query the table for an existing record. But I don't know how to check the record count from the sqlCommand I made.
Does that make sense?
Using myConnectionCheck As New SqlConnection(myConnectionStringCheck) Dim myCommandCheck As New SqlCommand() myCommandCheck.Connection = myConnectionCheck myCommandCheck.CommandText = "SELECT * FROM Req_Docs WHERE Doc_Name =" & DocName myConnectionCheck.Open() myCommandCheck.ExecuteNonQuery() End Using
On button click, I want to call a javascript code to check that If the entered BarCode Number in Textbox already exist in Database, then show an alert "Number already exist" else allow user to save and navigate to Default2.aspx
I can able to do the same checking on TextBox OnTextChanged event using c# code, as below:
protected void TextChanged(object sender, EventArgs e) { TextBox txtbarcode = fvIPRForm.FindControl("txtbarcodenumber") as TextBox; if (txtbarcode.Text.Length > 0 && txtbarcode.Text.Length < 11) { string error = "The Barcode Number " + txtbarcode.Text + " is invalid, the barcode length must be 11 character."; ScriptManager.RegisterStartupScript(this, typeof(string), "Successful", "alert('" + error + "');", true);
[Code] ....
Here, IPRRequest is the class/.dll file name and IsValidBarcodeTest is a function defined in the class file
But same checking I tried using the c# code on button's OnClick="btnSave_Click" event, but dont know why this event is not firing, I guess due to CommandArgument on button, but I am not sure.
I have two textboxes, one isfor 'program' and the other for 'description'. I have a predefined set of programs and it is associated descriptions in the database.
Example : For program named 'Test' it has the description as 'Valid' in the DB Table
For example, when enter a program name in the program textbox as 'Test', its associated description 'Valid' should be populated automatically to the 'Description' TextBox on losing focus from the 'Program' TextBox.
I tried to illustrate the problem by providing the following instructions, unfortunately the data was deleted and the example failed. It is now working. I have been working through one of Scott Mitchells ASP.NET Application Tutorials Title "Using TemplateFields in the GridView Control"
The URL is ...
The example demonstrates a temporary field being used in different ways, one of which involves dates in a Calender. If the HireDate in the example is deleted or not available the program fails. Providing the date is a valid date it works fine....
i am building a project using C# Asp.Net in which i am registering users with a user id, now my question is that how to check that the user id is already exists in the user table or not when user trying to register, i am using sql server 2000?
i have two datatable, while adding rows in second datatable, i want to first check whether the id in the second datatable matches as in the first datatable, if not only then it should be added in the second datatable, else it should display a message...
i dont have any Primary Key defined on any column, so the rows could be repeatative.
I am a beginner coder, i am building a project using C# Asp.Net in which i am registering users with a user id, now my question is that how to check that the user id is already exists in the user table or not when user trying to register, i am using sql server 2000?
