StringValidatorAttribute.MaxLength Property    
Definition
Important
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Gets or sets the maximum length allowed for the string to assign to the property.
public:
 property int MaxLength { int get(); void set(int value); };public int MaxLength { get; set; }member this.MaxLength : int with get, setPublic Property MaxLength As IntegerProperty Value
An integer that indicates the maximum allowed length for the string to assign to the property.
Exceptions
The selected value is less than MinLength.
Examples
The following example shows how to use the MaxLength property.
[ConfigurationProperty("fileName", DefaultValue = "default.txt",
    IsRequired = true, IsKey = false)]
[StringValidator(InvalidCharacters = " ~!@#$%^&*()[]{}/;'\"|\\",
    MinLength = 1, MaxLength = 60)]
public string FileName
{
    get
    {
        return (string)this["fileName"];
    }
    set
    {
        this["fileName"] = value;
    }
}
<ConfigurationProperty("fileName", _
DefaultValue:="default.txt", _
IsRequired:=True, _
IsKey:=False), _
StringValidator( _
InvalidCharacters:=" ~!@#$%^&*()[]{}/;'""|\", _
MinLength:=1, _
MaxLength:=60)> _
Public Property FileName() As String
    Get
        Return CStr(Me("fileName"))
    End Get
    Set(ByVal value As String)
        Me("fileName") = value
    End Set
End Property