ASP.Net/Validation by Control/By Your Function
Date validation: start, end date (C#)
<source lang="csharp">
<%@ Page language="c#" %> <%@ Import Namespace="System.Drawing" %>
<script language="c#" runat="server">
protected void ValidateTravelData(object source, System.Web.UI.WebControls.ServerValidateEventArgs args)
{
args.IsValid = false;
DateTime departDate, returnDate;
feedbackLabel.ForeColor = Color.Red;
try
{
departDate = DateTime.Parse(flightDepartureDateTextBox.Text);
} catch (Exception ex)
{
feedbackLabel.Text = "Invalid data entry: Departure Date is invalid. " +
"Enter a valid date, for example: 01/20/2006";
return;
}
try
{
returnDate = DateTime.Parse(flightReturnDateTextBox.Text);
} catch (Exception ex)
{
feedbackLabel.Text = "Invalid data entry: Return Date is invalid. " +
"Enter a valid date, for example: 01/20/2006";
return;
}
// Verify that the departure date is less than the
// return date - no same day trips in this system!
if (departDate >= returnDate)
{
feedbackLabel.Text = "Invalid data entry: The Departure Date must be " +
"earlier than the Return Date and no same-day " +
"returns for this travel package!";
return;
}
// Verify that the departure date is not in the past or today!
if (departDate < DateTime.Now)
{
feedbackLabel.Text = "Invalid data entry: The Departure Date cannot " +
"be in the past or today!";
return;
}
// Everthing is valid - set the IsValid flag...
args.IsValid = true;
}
private void bookTheTripButton_Click(object sender, EventArgs e)
{
// Has the page been validated for all data entry?
if (!(Page.IsValid))
{
return;
}
// We"re all set - book the flight!
DateTime departDate, returnDate;
departDate = DateTime.Parse(flightDepartureDateTextBox.Text);
returnDate = DateTime.Parse(flightReturnDateTextBox.Text);
feedbackLabel.ForeColor = Color.Black;
feedbackLabel.Text = "Success! Your trip from Chicago to London " +
"will depart on the " + departDate.ToLongDateString() +
" and return on the " + returnDate.ToLongDateString();
}</script>
<html> <head></head>
<body>
Travel: Chicago to London
<form id="TravelForm" method="post" runat="server">
<asp:panel id="Panel" runat="server" Width="504px" Height="89px"
BackColor="Wheat">Departure Date:
<asp:TextBox id="flightDepartureDateTextBox" runat="server"
Width="80px" Height="22px"/>Return Date:
<asp:TextBox id="flightReturnDateTextBox" runat="server"
Width="80px" Height="22px"/></br>
<asp:RequiredFieldValidator id="validateFlightDepartureDate" runat="server"
ErrorMessage="Please enter a valid Departure Date. "
ControlToValidate="flightDepartureDateTextBox" />
<asp:RequiredFieldValidator id="validateFlightReturnDate" runat="server"
ErrorMessage="Please enter a valid Return Date."
ControlToValidate="flightReturnDateTextBox" />
<asp:CustomValidator id="validateFlightDates" runat="server"
ControlToValidate="flightDepartureDateTextBox"
OnServerValidate="ValidateTravelData" />
</asp:panel>
<asp:Button id="bookTheTripButton" runat="server" Text="Book This Trip" OnClick="bookTheTripButton_Click" />
<asp:Label id="feedbackLabel" runat="server" BackColor="Wheat" Font-Bold="True" Text="Select your options, then click the "Book This Trip" button!" />
</form> </body>
</html>
</source>
Implement custom validation control event (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Protected Sub valProductCode_ServerValidate(ByVal source As Object, ByVal args As ServerValidateEventArgs)
If args.Value.Length = 4 Then
args.IsValid = True
Else
args.IsValid = False
End If
End Sub
</script> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1" runat="server">
<title>Show Validate Empty Text</title>
</head> <body>
<form id="form1" runat="server">
<asp:Label
id="lblProductCode"
Text="Product Code:"
AssociatedControlID="txtProductCode"
Runat="server" />
<asp:TextBox
id="txtProductCode"
Runat="server" />
<asp:CustomValidator
id="valProductCode"
ControlToValidate="txtProductCode"
Text="(Invalid product code)"
ValidateEmptyText="true"
OnServerValidate="valProductCode_ServerValidate"
Runat="server" />
<asp:Button
id="btnSubmit"
Text="Submit"
Runat="server" />
</form>
</body> </html>
</source>
Validate by a Server Validate function (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %> <script runat=server> Sub Answer_ServerValidation(source As object, E As ServerValidateEventArgs)
If E.Value = "VB" or E.Value = "VB.NET" or E.Value = "C#" _
or E.Value = "C#.NET" or E.Value = "A bunch of others." Then
E.IsValid = True
Else
E.IsValid = False
End If
End Sub
</SCRIPT>
<HTML>
<HEAD>
<TITLE>Using a RegularExpressionValidator Control to Test a Zip Code</TITLE>
</HEAD>
<form runat="server">
What languages can you use with ASP.NET?
<asp:textbox
id="txtAnswer" runat=server
/> <asp:customvalidator
id="custom9" controltovalidate="txtAnswer" OnServerValidate="Answer_ServerValidation" display="Dynamic" font-name="Verdana" font-bold="True" font-size="10pt" runat="server">
Incorrect answer please try again!
</asp:CustomValidator>
<asp:button
id="butOK" text="OK" type="Submit" runat="server"
/> </form> </BODY> </HTML>
</source>
Validate control in code behind in C#
<source lang="csharp">
<%@ Page language="c#" src="CustomerForm.aspx.cs" AutoEventWireup="false" Inherits="CustomerForm" %> <HTML>
<body> <form id="Form1" method="post" runat="server">
<asp:TextBox id="txtUserName" style="Z-INDEX: 101; LEFT: 160px; POSITION: absolute; TOP: 16px"
runat="server" Width="152px"></asp:TextBox>
<asp:Label id="Label1" style="Z-INDEX: 102; LEFT: 72px; POSITION: absolute; TOP: 19px" runat="server"
Font-Bold="True">User Name:</asp:Label>
<asp:TextBox id="txtPassword" style="Z-INDEX: 103; LEFT: 160px; POSITION: absolute; TOP: 56px"
runat="server" TextMode="Password" Width="152px"></asp:TextBox>
<asp:Label id="Label2" style="Z-INDEX: 104; LEFT: 80px; POSITION: absolute; TOP: 59px" runat="server"
Font-Bold="True">Password:</asp:Label>
<asp:TextBox id="txtRetype" style="Z-INDEX: 105; LEFT: 160px; POSITION: absolute; TOP: 88px"
runat="server" TextMode="Password" Width="152px"></asp:TextBox>
<asp:Label id="Label3" style="Z-INDEX: 106; LEFT: 13px; POSITION: absolute; TOP: 91px" runat="server"
Font-Bold="True">Password (retype):</asp:Label>
<asp:Label id="Label4" style="Z-INDEX: 107; LEFT: 104px; POSITION: absolute; TOP: 140px" runat="server"
Font-Bold="True">E-mail:</asp:Label>
<asp:TextBox id="txtEmail" style="Z-INDEX: 108; LEFT: 160px; POSITION: absolute; TOP: 136px"
runat="server" Width="152px"></asp:TextBox>
<asp:TextBox id="txtAge" style="Z-INDEX: 109; LEFT: 160px; POSITION: absolute; TOP: 176px" runat="server"
Width="152px"></asp:TextBox>
<asp:Label id="Label5" style="Z-INDEX: 110; LEFT: 117px; POSITION: absolute; TOP: 179px" runat="server"
Width="32px" Height="16px" Font-Bold="True">Age:</asp:Label>
<asp:Label id="Label6" style="Z-INDEX: 111; LEFT: 48px; POSITION: absolute; TOP: 228px" runat="server"
Width="106px" Height="24px" Font-Bold="True">Referrer Code:</asp:Label>
<asp:TextBox id="txtCode" style="Z-INDEX: 112; LEFT: 160px; POSITION: absolute; TOP: 224px" runat="server"
Width="152px"></asp:TextBox>
<asp:RequiredFieldValidator id="vldUserName" style="Z-INDEX: 113; LEFT: 336px; POSITION: absolute; TOP: 18px"
runat="server" ErrorMessage="You must enter a user name." ControlToValidate="txtUserName"></asp:RequiredFieldValidator>
<asp:RequiredFieldValidator id="vldPassword" style="Z-INDEX: 115; LEFT: 336px; POSITION: absolute; TOP: 59px"
runat="server" ErrorMessage="You must enter a password." ControlToValidate="txtPassword"></asp:RequiredFieldValidator>
<asp:CompareValidator id="vldRetype" style="Z-INDEX: 114; LEFT: 336px; POSITION: absolute; TOP: 93px"
runat="server" ErrorMessage="Your password does not match." ControlToCompare="txtPassword" ControlToValidate="txtRetype"></asp:CompareValidator>
<asp:RegularExpressionValidator id="vldEmail" style="Z-INDEX: 117; LEFT: 337px; POSITION: absolute; TOP: 139px"
runat="server" ErrorMessage="This email is missing the @ symbol." ValidationExpression=".+@.+" ControlToValidate="txtEmail"></asp:RegularExpressionValidator>
<asp:RangeValidator id="vldAge" style="Z-INDEX: 116; LEFT: 337px; POSITION: absolute; TOP: 180px" runat="server"
ErrorMessage="This age is not between 0 and 120." Type="Integer" MaximumValue="120" MinimumValue="0"
ControlToValidate="txtAge"></asp:RangeValidator>
<asp:CustomValidator id="vldCode" style="Z-INDEX: 118; LEFT: 337px; POSITION: absolute; TOP: 227px" runat="server"
ErrorMessage="Try a string that starts with 014." ControlToValidate="txtCode" ClientValidationFunction="MyCustomValidation"></asp:CustomValidator>
<asp:Button id="cmdSubmit" style="Z-INDEX: 119; LEFT: 160px; POSITION: absolute; TOP: 304px"
runat="server" Width="120px" Text="Submit"></asp:Button>
<asp:Button id="cmdCancel" style="Z-INDEX: 120; LEFT: 304px; POSITION: absolute; TOP: 304px"
runat="server" Width="121px" Height="24px" Text="Cancel" CausesValidation="False"></asp:Button> <asp:Label id="lblMessage" style="Z-INDEX: 102; LEFT: 24px; POSITION: absolute; TOP: 388px"
runat="server" Width="616px" Height="72px"></asp:Label>
</form>
</body>
</HTML>
<%-- CustomerForm.aspx.cs using System; using System.Collections; using System.ruponentModel; using System.Data; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls;
public class CustomerForm : System.Web.UI.Page
{
protected System.Web.UI.WebControls.TextBox txtUserName;
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.TextBox txtPassword;
protected System.Web.UI.WebControls.Label Label2;
protected System.Web.UI.WebControls.TextBox txtRetype;
protected System.Web.UI.WebControls.Label Label3;
protected System.Web.UI.WebControls.Label Label4;
protected System.Web.UI.WebControls.TextBox txtEmail;
protected System.Web.UI.WebControls.TextBox txtAge;
protected System.Web.UI.WebControls.Label Label5;
protected System.Web.UI.WebControls.Label Label6;
protected System.Web.UI.WebControls.TextBox txtCode;
protected System.Web.UI.WebControls.RequiredFieldValidator vldUserName;
protected System.Web.UI.WebControls.RequiredFieldValidator vldPassword;
protected System.Web.UI.WebControls.rupareValidator vldRetype;
protected System.Web.UI.WebControls.RegularExpressionValidator vldEmail;
protected System.Web.UI.WebControls.RangeValidator vldAge;
protected System.Web.UI.WebControls.CustomValidator vldCode;
protected System.Web.UI.WebControls.Button cmdSubmit;
protected System.Web.UI.WebControls.Button cmdCancel;
protected System.Web.UI.WebControls.Label lblMessage;
private void Page_Load(object sender, System.EventArgs e)
{
// Put user code to initialize the page here
}
#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.vldCode.ServerValidate += new System.Web.UI.WebControls.ServerValidateEventHandler(this.vldCode_ServerValidate);
this.cmdSubmit.Click += new System.EventHandler(this.cmdSubmit_Click);
this.cmdCancel.Click += new System.EventHandler(this.cmdCancel_Click);
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
private void cmdSubmit_Click(object sender, System.EventArgs e)
{
if (!this.IsValid) return;
lblMessage.Text = "This is a valid form.";
}
private void cmdCancel_Click(object sender, System.EventArgs e)
{
lblMessage.Text = "No attempt was made to validate this form.";
}
private void vldCode_ServerValidate(object source, System.Web.UI.WebControls.ServerValidateEventArgs e)
{
try{
int val = Int32.Parse(e.Value.Substring(0, 3));
if (val % 3 == 0){
e.IsValid = true;
}else{
e.IsValid = false;
}
}catch{
e.IsValid = false;
}
}
}
--%>
</source>
Validate control manually in C#
<source lang="csharp">
<%@ Page language="c#" src="ManualValidation.aspx.cs" AutoEventWireup="false" Inherits="ManualValidation" %> <HTML>
<body>
<form id="Form1" method="post" runat="server">
A number (1 to 10):
<asp:TextBox id="txtValidated" runat="server"></asp:TextBox>
<asp:RangeValidator id="RangeValidator" runat="server" ErrorMessage="This Number Is Not In The Range" ControlToValidate="txtValidated" MaximumValue="10" MinimumValue="1" Type="Integer" EnableClientScript="False"></asp:RangeValidator>
Not validated:
<asp:TextBox id="txtNotValidated" runat="server"></asp:TextBox>
<asp:Button id="cmdOK" runat="server" Text="OK"></asp:Button>
<asp:Label id="lblMessage" runat="server" EnableViewState="False"></asp:Label>
</form>
</body>
</HTML> <%-- using System; using System.Collections; using System.ruponentModel; using System.Data; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls;
public class ManualValidation : System.Web.UI.Page
{
protected System.Web.UI.WebControls.TextBox txtValidated;
protected System.Web.UI.WebControls.RangeValidator RangeValidator;
protected System.Web.UI.WebControls.TextBox txtNotValidated;
protected System.Web.UI.WebControls.Button cmdOK;
protected System.Web.UI.WebControls.Label lblMessage;
private void Page_Load(object sender, System.EventArgs e)
{
// Put user code to initialize the page here
}
#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.cmdOK.Click += new System.EventHandler(this.cmdOK_Click);
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
private void cmdOK_Click(object sender, System.EventArgs e)
{
string errorMessage = "Mistakes found:
";
TextBox ctrlInput;
bool pageIsValid = true;
foreach (BaseValidator ctrl in this.Validators)
{
if (!ctrl.IsValid)
{
pageIsValid = false;
errorMessage += ctrl.ErrorMessage + "
";
ctrlInput = (TextBox)this.FindControl(ctrl.ControlToValidate);
errorMessage += " * Problem is with this input: ";
errorMessage += ctrlInput.Text + "
";
}
}
if (!pageIsValid) lblMessage.Text = errorMessage;
}
}
--%>
</source>
Validating a Percentage Using the CustomValidator Control (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %> <script runat=server> Sub Answer_ServerValidation(source As object, E As ServerValidateEventArgs)
Dim TheNumber as Single
If Right(E.Value, 1) = "%" Then
TheNumber = Left(E.Value, Len(E.Value) - 1)
If TheNumber > 100 or TheNumber < 0 Then
E.IsValid = False
Else
E.IsValid = True
End If
Else
E.IsValid = False
End If
End Sub
</SCRIPT>
<HTML>
<HEAD>
<TITLE>Validating a Percentage Using the CustomValidator Control</TITLE>
</HEAD>
<form runat="server">
Enter a Percentage up to 100%:
<asp:textbox
id="txtAnswer" runat=server
/> <asp:customvalidator
id="custom9" controltovalidate="txtAnswer" OnServerValidate="Answer_ServerValidation" display="Dynamic" font-name="Verdana" font-bold="True" font-size="10pt" runat="server">
Incorrect answer please try again!
</asp:CustomValidator>
<asp:button
id="butOK" text="OK" type="Submit" runat="server"
/> </form> </BODY> </HTML>
</source>
