【Telerik】查询控件<telerik:RadMaskedTextBox>的使用

在SilverLight项目中，实现模糊查询，并将值绑定到列表中，使用了Telerik中的<telerik:RadMaskedTextBox>控件。

要先添加命名空间的引用： xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"

并且项目要添加引用：

xaml页面代码：

 <!-- 检索-->
                    <Border>
                        <Grid HorizontalAlignment="Left" Width="150">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="Auto"></ColumnDefinition>
                                <ColumnDefinition></ColumnDefinition>
                            </Grid.ColumnDefinitions>
                            <Image  Grid.Column="0" Source="/MASP;Component/Images/Find.png" Stretch="Uniform" Margin="4"></Image>
                            <telerik:RadMaskedTextBox  x:Name="mask_treat" Grid.Column="1" Margin="3" BorderThickness="0" 
EmptyContent="输入关键字进行检索" MaskType="None" VerticalAlignment="Center" ValueChanged="mask_treat_ValueChanged"></telerik:RadMaskedTextBox>
                        </Grid>
                    </Border>

xaml.cs代码：文本内容发生改变事件ValueChanged

 private void mask_treat_ValueChanged(object sender, Telerik.Windows.RadRoutedEventArgs e)
        {
            try
            {
                string value = mask_treat.MaskedText == null ? "" : mask_treat.MaskedText.ToString().Trim();

                IList<GridViewDataColumn> ViewDataColumns = new List<GridViewDataColumn>();
                ViewDataColumns.Add(Rgv_treatlist.Columns[2] as GridViewDataColumn);
                ViewDataColumns.Add(Rgv_treatlist.Columns[3] as GridViewDataColumn);
                ViewDataColumns.Add(Rgv_treatlist.Columns[4] as GridViewDataColumn);
                CustomFilterDescriptor FilterDescriptor = new CustomFilterDescriptor(ViewDataColumns);
                FilterDescriptor.FilterValue = value;
                Rgv_treatlist.FilterDescriptors.Clear();
                Rgv_treatlist.FilterDescriptors.Add(FilterDescriptor);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

CustomFilterDescriptor类代码：

using Telerik.Windows.Controls;
using Telerik.Windows.Data;  

public class CustomFilterDescriptor : FilterDescriptorBase
    {
        private readonly CompositeFilterDescriptor compositeFilterDesriptor;
        private static readonly ConstantExpression TrueExpression = System.Linq.Expressions.Expression.Constant(true);
        private string filterValue;

        public CustomFilterDescriptor(IEnumerable<Telerik.Windows.Controls.GridViewColumn> columns)
        {
            this.compositeFilterDesriptor = new CompositeFilterDescriptor();
            this.compositeFilterDesriptor.LogicalOperator = FilterCompositionLogicalOperator.Or;

            foreach (GridViewDataColumn column in columns)
            {
                this.compositeFilterDesriptor.FilterDescriptors.Add(this.CreateFilterForColumn(column));
            }
        }

        public string FilterValue
        {
            get
            {
                return this.filterValue;
            }
            set
            {
                if (this.filterValue != value)
                {
                    this.filterValue = value;
                    this.UpdateCompositeFilterValues();
                    this.OnPropertyChanged("FilterValue");
                }
            }
        }

        protected override System.Linq.Expressions.Expression CreateFilterExpression(ParameterExpression parameterExpression)
        {
            if (string.IsNullOrEmpty(this.FilterValue))
            {
                return TrueExpression;
            }
            try
            {
                return this.compositeFilterDesriptor.CreateFilterExpression(parameterExpression);
            }
            catch
            {
            }

            return TrueExpression;
        }

        private IFilterDescriptor CreateFilterForColumn(GridViewDataColumn column)
        {
            FilterOperator filterOperator = GetFilterOperatorForType(column.DataType);
            FilterDescriptor descriptor = new FilterDescriptor(column.UniqueName, filterOperator, this.filterValue);
            descriptor.MemberType = column.DataType;

            return descriptor;
        }


        private static FilterOperator GetFilterOperatorForType(Type dataType)
        {
            return dataType == typeof(string) ? FilterOperator.Contains : FilterOperator.IsEqualTo;
        }

        private void UpdateCompositeFilterValues()
        {
            foreach (FilterDescriptor descriptor in this.compositeFilterDesriptor.FilterDescriptors)
            {
                object convertedValue = DefaultValue(descriptor.MemberType);

                try
                {
                    convertedValue = Convert.ChangeType(this.FilterValue, descriptor.MemberType, null);
                }
                catch
                {
                }

                if (!descriptor.MemberType.IsAssignableFrom(typeof(DateTime)))
                {
                    descriptor.Value = convertedValue; ;

                }
            }
        }

        private static object DefaultValue(Type type)
        {
            if (type.IsValueType)
            {
                return Activator.CreateInstance(type);
            }

            return null;
        }
    }

记录完成。