Introduction: In this article i
am going to explain with example How to maintain or preserve the password value in
the TextBox controls during/on/while/even after the occurrence of post back event in asp.net using both C# and VB.Net languages. I have also explained how to clear maintained password on cancel or reset button click.
In previous articles i explained How to Show hide password characters in textbox on checkbox check uncheck using jQuery and Create change password form in asp.net and Implement remember me next time checkbox option In login form and Recover and reset the forgot/lost password in using activation link in email and Using ajax password strength indicator in asp.net for password field
Description: While working on project i got the requirement to create a registration form having the TextBox for User Name, Password, Confirm Password and DropDownList for State and City.
In previous articles i explained How to Show hide password characters in textbox on checkbox check uncheck using jQuery and Create change password form in asp.net and Implement remember me next time checkbox option In login form and Recover and reset the forgot/lost password in using activation link in email and Using ajax password strength indicator in asp.net for password field
Description: While working on project i got the requirement to create a registration form having the TextBox for User Name, Password, Confirm Password and DropDownList for State and City.
The
AutoPostback property of the State DropDownList was set to true so that corresponding cities can be populated in the city DropDownList based on the selected state.
But i faced an issue that whenever i select any State then post back occurs due to the AutoPostbBck propery of the DropDownList, the entered values from the Password and Confirm Password TextBox get cleared. Actually it is the default nature of the TextBox control whose TextMode property is set to password.
But i want to maintain whatever password i have entered in the textbox across postback. Here in this article i have explained the solution for this problem. Inside page load event i first checked whether it is postback, if yes then i am setting the value attribute of textbox with the value of password textbox.
But i faced an issue that whenever i select any State then post back occurs due to the AutoPostbBck propery of the DropDownList, the entered values from the Password and Confirm Password TextBox get cleared. Actually it is the default nature of the TextBox control whose TextMode property is set to password.
But i want to maintain whatever password i have entered in the textbox across postback. Here in this article i have explained the solution for this problem. Inside page load event i first checked whether it is postback, if yes then i am setting the value attribute of textbox with the value of password textbox.
However retaining password is considered to be
security hole so it is not preferable to retain password between post backs.
Note: I have not implemented the
functionality of filling state and city from the database and just
added the State and City statically. If you want so then read the
articles
Implementation: Let's create an
asp.net sample website to see it in action.
In the design page (.aspx) design
the page as:
HTML Source Code:
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<fieldset
style="width:
320px;">
<legend>Maintain password after postback</legend>
<table>
<tr>
<td>UserName</td>
<td>
<asp:TextBox ID="txtUserName" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>Password</td>
<td>
<asp:TextBox ID="txtPwd" runat="server" TextMode="Password"></asp:TextBox>
</td>
</tr>
<tr>
<td>Confirm Password</td>
<td>
<asp:TextBox ID="txtConfirmPwd" runat="server" TextMode="Password"></asp:TextBox>
</td>
</tr>
<tr>
<td>State</td>
<td>
<asp:DropDownList ID="ddlState" Width="172px" runat="server" AutoPostBack="True">
<asp:ListItem Text="Select" Value="0"></asp:ListItem>
<asp:ListItem Text="Haryana" Value="1"></asp:ListItem>
<asp:ListItem Text="Punjab" Value="2"></asp:ListItem>
<asp:ListItem Text="Himachal" Value="3"></asp:ListItem>
</asp:DropDownList>
</td>
</tr>
<tr>
<td>City</td>
<td>
<asp:DropDownList ID="ddlCity" Width="172px" runat="server">
<asp:ListItem Text="Select" Value="0"></asp:ListItem>
<asp:ListItem
Text="Panchkula" Value="1"></asp:ListItem>
<asp:ListItem Text="Ambala" Value="2"></asp:ListItem>
<asp:ListItem Text="Kalka" Value="3"></asp:ListItem>
</asp:DropDownList>
</td>
</tr>
<tr>
<td></td>
<td>
<asp:Button ID="btnSubmit" runat="server" Text="Submit"
OnClick="btnSubmit_Click" />
<asp:Button ID="btnCancel" runat="server" Text="Cancel"
OnClick="btnCancel_Click" />
</td>
</tr>
</table>
</fieldset>
</div>
</form>
</body>
</html>
Asp.Net C# code to keep the password even after Postback
- In the code behind file(.aspx.cs) write the code as :
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
if (!(String.IsNullOrEmpty(txtPwd.Text.Trim())))
{
txtPwd.Attributes["value"] = txtPwd.Text;
//or
txtPwd.Attributes.Add("value",txtPwd.Text);
}
if (!(String.IsNullOrEmpty(txtConfirmPwd.Text.Trim())))
{
txtConfirmPwd.Attributes["value"] = txtConfirmPwd.Text;
//or
txtConfirmPwd.Attributes.Add("value", txtConfirmPwd.Text);
}
}
}
protected void btnSubmit_Click(object
sender, EventArgs e)
{
// Write your code
here;
}
protected void btnCancel_Click(object
sender, EventArgs e)
{
txtUserName.Text = txtPwd.Text =
txtConfirmPwd.Text = string.Empty;
txtPwd.Attributes.Remove("value");
txtConfirmPwd.Attributes.Remove("value");
ddlState.ClearSelection();
ddlCity.ClearSelection();
}
Asp.Net VB Code keep the password even after Postback
- In the code behind file(.aspx.vb) write the code as:
Protected Sub Page_Load(sender As Object,
e As EventArgs)
Handles
Me.Load
If IsPostBack Then
If Not ([String].IsNullOrEmpty(txtPwd.Text.Trim())) Then
'or
txtPwd.Attributes.Add("value",txtPwd.Text);
txtPwd.Attributes("value") = txtPwd.Text
End If
If Not ([String].IsNullOrEmpty(txtConfirmPwd.Text.Trim()))
Then
'or
txtConfirmPwd.Attributes.Add("value", txtConfirmPwd.Text);
txtConfirmPwd.Attributes("value") = txtConfirmPwd.Text
End If
End If
End Sub
Protected Sub btnSubmit_Click(sender As Object,
e As EventArgs)
Handles
btnSubmit.Click
' Write your code
here;
End Sub
Protected Sub btnCancel_Click(sender As Object,
e As EventArgs)
Handles
btnCancel.Click
txtUserName.Text = String.Empt
txtPwd.Text= String.Empty
txtConfirmPwd.Text=
String.Empty
txtPwd.Attributes.Remove("value")
txtConfirmPwd.Attributes.Remove("value")
ddlState.ClearSelection()
ddlCity.ClearSelection()
End Sub
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3 comments
Click here for commentsUseful document.it could help us to keep things in mind.
ReplyUseful document.it could help us to keep things in mind.
ReplyThanks for you feedback..I am glad you liked this article..stay connected and keep reading for more useful updates like this.
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