关于WPF使用MultiConverter控制Button状态的详细介绍

  需求描述

  1.按钮的状态需要根据多个数据源的内容作出不同的组合判断

  2.每个数据源的判断规则可定制

  注:以下功能感觉只是简单粗暴的实现,如果您了解更优雅的解决方案,烦请告诉我下,感谢先!

  按钮XAML

  

复制代码 代码如下:

  <Button Name="btnOK"

  Grid.Column="2"

  HorizontalAlignment="Left"

  VerticalAlignment="Center"

  Command="{Binding Path=OKCommand}"

  Content="{DynamicResource Common_Button_OK}"

  IsDefault="True"

  Style="{DynamicResource ButtonStyle}">

  <Button.IsEnabled>

  <MultiBinding Converter="{StaticResource InvalidMultiValidationRuleToBooleanMultiConverter}"

  ConverterParameter="objectnull|greaterthanzerointeger|greaterthanzerointeger|greaterthanzerointeger">

  <Binding ElementName="comboBoxFilter"

  Mode="OneWay"

  Path="SelectedItem" />

  <Binding ElementName="textBoxFrameRate"

  Mode="OneWay"

  Path="Text" />

  <Binding ElementName="textBoxSizeWidth"

  Mode="OneWay"

  Path="Text" />

  <Binding ElementName="textBoxSizeHeight"

  Mode="OneWay"

  Path="Text" />

  </MultiBinding>

  </Button.IsEnabled>

  </Button>

  MultiConverter判断

  

复制代码 代码如下:

  public class InvalidMultiValidationRuleToBooleanMultiConverter : IMultiValueConverter

  {

  #region IMultiValueConverter Members

  public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)

  {

  string[] paramlist = ((string)parameter).Split('|');

  if (paramlist == null || paramlist.Length <= 0)

  {

  throw new ArgumentNullException("parameter");

  }

  int length = paramlist.Length;

  IList<bool> boollist = new List<bool>();

  for (int i = 0; i < paramlist.Length; i++)

  {

  switch (paramlist[i].ToLowerInvariant())

  {

  case "checknameexisted":

  boollist.Add(ValidationRuleHelper.Validate<InvalidCheckNameExistedValidationRule>(values[i]));

  break;

  case "directoryandfileexist":

  boollist.Add(ValidationRuleHelper.Validate<InvalidDirectoryAndFileExistValidationRule>(values[i]));

  break;

  case "greaterthanzerointeger":

  boollist.Add(ValidationRuleHelper.Validate<InvalidGreaterThanZeroIntegerValidationRule>(values[i]));

  break;

  case "numericnull":

  boollist.Add(ValidationRuleHelper.Validate<InvalidNumericNullValidationRule>(values[i]));

  break;

  case "stringlength":

  boollist.Add(ValidationRuleHelper.Validate<InvalidStringLengthValidationRule>(values[i]));

  break;

  case "stringnullorempty":

  boollist.Add(ValidationRuleHelper.Validate<InvalidStringNullOrEmptyValidationRule>(values[i]));

  break;

  case "ipaddress":

  boollist.Add(ValidationRuleHelper.Validate<InvalidIPAddressValidationRule>(values[i]));

  break;

  case "objectnull":

  default:

  boollist.Add(ValidationRuleHelper.Validate<InvalidObjectNullValidationRule>(values[i]));

  break;

  }

  }

  bool result = boollist[0];

  for (int i = 1; i < boollist.Count; i++)

  {

  result = result & boollist[i];

  }

  return result;

  }

  public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)

  {

  return null;

  }

  #endregion

  }