RangeValidator

@inherits ControlComponent
<p>Enter a number from 1 to 10:</p>

<br />

<asp.TextBox ID="TextBox1" />

<br />

<asp.RangeValidator ControlToValidate="TextBox1"
                                            MinimumValue="1"
                                            MaximumValue="10"
                                            Type="ValidationDataType.Integer"
                                            EnableClientScript="false"
                                            Text="The value must be from 1 to 10!" />

<br />
<br />

<asp.Label @ref="this.label1" />

<br />
<br />

<asp.Button Text="Submit"
                                            OnClick="this.ButtonClick" />

@code {
                                            private Label label1;

                                            protected void ButtonClick(object sender, EventArgs e)
    {
                                            if (this.Page.IsValid)
        {
            label1.Text = "Page is valid.";
        }
                                            else
        {
            label1.Text = "Page is not valid!!";
        }
    }
}