The Asp.net regularexpressionvalidator control verifies that the input value matches the pattern specified by the regular expression.

The RegularExpressionValidator control is used to verify whether the input value matches the pattern specified by the regular expression.

Attribute:

ControlToValidate = "Name of the control to be verified"
ValidationExpression = "verification rules"
ErrorMessage = "error message to be displayed"

Text = "message displayed when verification fails ."

ForeColor = "color of the prompt message"

Page Structure:

 

HTML code:

<% -- Add button -- %>

<Asp: Button ID = "btnAdd" runat = "server" Text = "" onclick = "btnAdd_Click" ValidationGroup = "checkText"/>

<% -- The project name must be a Chinese character, and the maximum number of people must be a number -- %>
<Asp: regularExpressionValidator ID = "regular" runat = "server" ValidationGroup = "checkText" ControlToValidate = "txtEventName" ErrorMessage = "* The project name can only contain Chinese characters" ValidationExpression = "^ [\ 1- \ tags] {0 ,} $ "/>

<% -- The maximum number of verified reports must be a number -- %>

<Asp: regularExpressionValidator ID = "regular" runat = "server" ValidationGroup = "checkText" ControlToValidate = "txtLimitNum" ErrorMessage = "* The number of people must be a number" validationexpression = "^ [0-9] * $ "> </asp: regularExpressionValidator>

<% -- Control time format -- %>
<Asp: regularExpressionValidator ID = "regular" runat = "server" ValidationGroup = "checkText" ControlToValidate = "txtTime" ErrorMessage = "* the time must be in the format of" validationexpression = "^ (\ d {4 }) -(0 \ d {1} | 1 [0-2])-(0 \ d {1} | [12] \ d {1} | 3 [01]) $ "> </asp: RegularExpressionValidator>

<% -- Verify that the competition location must be a Chinese character -- %>
<Asp: regularExpressionValidator ID = "RegularExpressionValidator4" runat = "server" ValidationGroup = "checkText" ControlToValidate = "txtPlace" ErrorMessage = "* only Chinese characters can be entered at the competition location- \ tags] {0 ,} $ "/>

The above verification only serves as a prompt and does not prevent button addition. Therefore, the validationSummary control should be used to display the verification error message through Messagebox to avoid executing button_click ().

<% -- If the verification fails, the error message (ShowMessageBox = "true") "is displayed in the prompt box -- %>
<Asp: ValidationSummary ID = "ValidationSummary1" ValidationGroup = "checkText" ShowMessageBox = "true" ShowSummary = "false" runat = "server"/>