A validator is a computer program used to check the validity or syntactical correctness of a fragment of code or text.
IN ASP.NET there are six different types of Validators.
Required Field Validator.
Regular Expression Validator.
Compare Validator.
Range Validator.
CustomValidator.
Validation Summary
RequiredFieldValidator:-Ensure that the control has a value to assign in it or user does not skip an entry.
For Example:-
<asp:Textbox id="txtMobileNumber" runat="server"></asp:Textbox>
<asp:RequiredFieldValidator id="RequiredFieldValidator1" runat="server"
ControlToValidate="txtMobileNumber"
ErrorMessage="Mobile Number is a required field."
ForeColor="Red">
</asp:RequiredFieldValidator>
RegularExpressionValidator:-Ensure that the value of the control matches the expression of validator that is specified.This type of validation enables you to check for sequence of character, such as e-mail address,telephone number,postal code and so on.
For Example:-
<asp:TextBox ID="txtE-Mail" runat="server"></asp:TextBox>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server"
ControlToValidate="txtPassword"
ErrorMessage="Please Enter a Valid E-Mail"
ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"> // for internet E-Mail.
</asp:RegularExpressionValidator>
CompareValidator:-Ensure that the value of one control should be equal to value of another control.which is commonly used in password,less than,greater than or equal to.
For Example:-
<asp:TextBox ID="txtPassword" runat="server"></asp:TextBox>
<asp:TextBox ID="txtConfirmPassword" runat="server"></asp:TextBox>
<asp:CompareValidator ID="CompareValidator1" runat="server"
ControlToCompare="txtPassword" ControlToValidate="txtConfirmPassword"
ErrorMessage="Password does not match">
</asp:CompareValidator>
RangeValidator:-Ensures that the value of the control is in specified lower and upper boundaries or specified range. You can check ranges within pairs of numbers, alphabetic characters.
For Example:-
<asp:TextBox ID="txtAmount" runat="server"></asp:TextBox>
<asp:RangeValidator ID="RangeValidator1" runat="server"
ControlToValidate="txtPassword"
ErrorMessage="RangeValidator" MaximumValue="5000"
MinimumValue="100">
</asp:RangeValidator>>
CustomValidator:-This control is used to perform user defined validations.
ValidationSummary:-This validator is used to displays a detailed summary on the validation errors that currently exist.
Regards,