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HtmlInputText.MaxLength Property

Definition

Gets or sets the maximum number of characters that can be entered in the text box.

public:
 property int MaxLength { int get(); void set(int value); };
public int MaxLength { get; set; }
member this.MaxLength : int with get, set
Public Property MaxLength As Integer

Property Value

The maximum number of characters that can be entered in the text box.

Examples

The following code example demonstrates how to use the MaxLength property to specify the maximum number of characters that can be entered in the text box.

<%@ Page Language="C#" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    protected void AddButton_Click(Object sender, EventArgs e)
    {
        int Answer;

        Answer = Convert.ToInt32(Value1.Value) + 
            Convert.ToInt32(Value2.Value);
        AnswerMessage.InnerHtml = Answer.ToString();

    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" > 
<head>
    <title> HtmlInputText Example </title>
</head>
<body>
<form id="form1" runat="server">
    <div>

    <h3> HtmlInputText Example </h3>

    <table>
        <tr>
            <td colspan="5">

               Enter integer values into the text boxes. <br />
               Click the Add button to add the two values. <br />
               Click the Reset button to reset the text boxes.

            </td>
       </tr>
       <tr>
            <td colspan="5">
                 

            </td>
       </tr>
       <tr align="center">
            <td>

               <input id="Value1"
                      type="Text"
                      size="2"
                      maxlength="3"
                      value="1"
                      runat="server"/>

            </td>
            <td>
                + 
            </td>
            <td>

               <input id="Value2"
                      type="Text"
                      size="2"
                      maxlength="3"
                      value="1"
                      runat="server"/>

            </td>
            <td>
                =
            </td>
            <td>
               
               <span id="AnswerMessage"
                     runat="server"/>

            </td>
        </tr>
        <tr>
            <td colspan="2">

               <asp:RequiredFieldValidator
                    ID="Value1RequiredValidator"
                    ControlToValidate="Value1"
                    ErrorMessage="Please enter a value.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value1MinCompareValidator"
                    ControlToValidate="Value1"
                    Operator="LessThan"
                    Type="Integer"
                    ValueToCompare="100"
                    ErrorMessage="Please enter an integer less than 100.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value1MaxCompareValidator"
                    ControlToValidate="Value1"
                    Operator="GreaterThan"
                    Type="Integer"
                    ValueToCompare="0"
                    ErrorMessage="Please enter an integer greater than 0.<br />"
                    Display="Dynamic"
                    runat="server"/>

            </td>
            <td colspan="2">

               <asp:RequiredFieldValidator
                    ID="Value2RequiredValidator"
                    ControlToValidate="Value2"
                    ErrorMessage="Please enter a value.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value2MinCompareValidator"
                    ControlToValidate="Value2"
                    Operator="LessThan"
                    Type="Integer"
                    ValueToCompare="100"
                    ErrorMessage="Please enter an integer less than 100.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value2MaxCompareValidator"
                    ControlToValidate="Value2"
                    Operator="GreaterThan"
                    Type="Integer"
                    ValueToCompare="0"
                    ErrorMessage="Please enter an integer greater than 0.<br />"
                    Display="Dynamic"
                    runat="server"/>

            </td>
            <td>
                 
            </td>
        </tr>
        <tr align="center">
            <td colspan="4">

                <input type="Submit"
                      name="AddButton"
                      value="Add"
                      onserverclick="AddButton_Click"
                      runat="server"/>

                   

                <input type="Reset"
                      name="AddButton"
                      value="Reset"
                      runat="server"/>

            </td>
            <td>
                 
            </td>
        </tr>
    </table>

    </div>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    Protected Sub AddButton_Click(sender As Object, e As EventArgs)

        Dim Answer As Integer

        Answer = Convert.ToInt32(Value1.Value) + Convert.ToInt32(Value2.Value)
        AnswerMessage.InnerHtml = Answer.ToString()

    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" > 
<head>
    <title> HtmlInputText Example </title>
</head>
<body>
<form id="form1" runat="server">
    <div>

    <h3> HtmlInputText Example </h3>

    <table>
        <tr>
            <td colspan="5">

               Enter integer values into the text boxes. <br />
               Click the Add button to add the two values. <br />
               Click the Reset button to reset the text boxes.

            </td>
       </tr>
       <tr>
            <td colspan="5">
                 

            </td>
       </tr>
       <tr align="center">
            <td>

               <input id="Value1"
                      type="Text"
                      size="2"
                      maxlength="3"
                      value="1"
                      runat="server"/>

            </td>
            <td>
                + 
            </td>
            <td>

               <input id="Value2"
                      type="Text"
                      size="2"
                      maxlength="3"
                      value="1"
                      runat="server"/>

            </td>
            <td>
                =
            </td>
            <td>
               
               <span id="AnswerMessage"
                     runat="server"/>

            </td>
        </tr>
        <tr>
            <td colspan="2">

               <asp:RequiredFieldValidator
                    ID="Value1RequiredValidator"
                    ControlToValidate="Value1"
                    ErrorMessage="Please enter a value.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value1MinCompareValidator"
                    ControlToValidate="Value1"
                    Operator="LessThan"
                    Type="Integer"
                    ValueToCompare="100"
                    ErrorMessage="Please enter an integer less than 100.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value1MaxCompareValidator"
                    ControlToValidate="Value1"
                    Operator="GreaterThan"
                    Type="Integer"
                    ValueToCompare="0"
                    ErrorMessage="Please enter an integer greater than 0.<br />"
                    Display="Dynamic"
                    runat="server"/>

            </td>
            <td colspan="2">

               <asp:RequiredFieldValidator
                    ID="Value2RequiredValidator"
                    ControlToValidate="Value2"
                    ErrorMessage="Please enter a value.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value2MinCompareValidator"
                    ControlToValidate="Value2"
                    Operator="LessThan"
                    Type="Integer"
                    ValueToCompare="100"
                    ErrorMessage="Please enter an integer less than 100.<br />"
                    Display="Dynamic"
                    runat="server"/>

               <asp:CompareValidator
                    ID="Value2MaxCompareValidator"
                    ControlToValidate="Value2"
                    Operator="GreaterThan"
                    Type="Integer"
                    ValueToCompare="0"
                    ErrorMessage="Please enter an integer greater than 0.<br />"
                    Display="Dynamic"
                    runat="server"/>

            </td>
            <td>
                 
            </td>
        </tr>
        <tr align="center">
            <td colspan="4">

                <input type="Submit"
                      name="AddButton"
                      value="Add"
                      onserverclick="AddButton_Click"
                      runat="server"/>

                   

                <input type="Reset"
                      name="AddButton"
                      value="Reset"
                      runat="server"/>

            </td>
            <td>
                 
            </td>
        </tr>
    </table>

    </div>
</form>
</body>
</html>

Remarks

Use the MaxLength property to specify or determine the maximum number of characters that can be entered in the text box.

Applies to

See also