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HtmlInputText.MaxLength Свойство

Определение

Получает или задает наибольшее количество знаков, которое можно ввести в данное текстовое поле.

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

Значение свойства

Наибольшее число знаков, которое можно ввести в данное текстовое поле.

Примеры

В следующем примере кода показано, как использовать MaxLength свойство для указания максимального количества символов, которые можно ввести в текстовое поле.

<%@ 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>

Комментарии

Используйте свойство , MaxLength чтобы указать или определить максимальное количество символов, которые можно ввести в текстовое поле.

Применяется к

См. также раздел