使用Telerik RadGridView對不區分大小寫和變音符號進行不敏感過濾

Question

標題幾乎說明了一切。 如何使用Telerik RadGridView對不區分大小寫和變音符號進行不敏感過濾？

我找到了許多與谷歌有關的可行解決方案，但它們都不易使用，而且，在許多情況下，它改變了RadGridView的UI行為，使其對最終用戶的吸引力降低。

Answer 1

多年來，我的經驗和技能都有所增長，最后我想出了一個簡單易用的解決方案。 它適用於Telerik UI for WinForms 2017 R1或更新版本，以及Visual Studio 2015或更新版本。

這是輔助類RadGridViewHelper ：

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Globalization;
using System.Linq;
using Telerik.WinControls.Data;
using Telerik.WinControls.UI;

namespace MySoftware.Helpers
{
    internal static class RadGridViewHelper
    {
        private class CustomStringFilteringClass
        {
            private RadGridView RadGridView { get; }
            private bool _enabled;
            private ReadOnlyCollection<string> StringColumns { get; }

            public CustomStringFilteringClass(RadGridView radGridView)
            {
                RadGridView = radGridView;
                StringColumns = new ReadOnlyCollection<string>(GetStringColumns(radGridView));
            }

            public void Enable()
            {
                if (_enabled) throw new InvalidOperationException("Can't call this method twice");
                _enabled = true;

                RadGridView.EnableCustomFiltering = true;
                RadGridView.CustomFiltering += RadGridViewOnCustomFiltering;
            }

            private void RadGridViewOnCustomFiltering(object sender, GridViewCustomFilteringEventArgs e)
            {
                if (RadGridView.FilterDescriptors.Count == 0) return;

                var row = e.Row;

                foreach (var stringColumn in StringColumns)
                {
                    var filterDescriptors = RadGridView.FilterDescriptors.Where(
                        x => x.PropertyName == stringColumn).ToList();
                    if (filterDescriptors.Count != 1)
                    {
                        continue;
                    }
                    var filterDescriptor = filterDescriptors.First();
                    var cellValue = ((string) row.Cells[stringColumn].Value).ToLowerInvariant();
                    if (filterDescriptor.GetType() == typeof(CompositeFilterDescriptor))
                    {
                        if (!CompositeFilterEvaluateString((CompositeFilterDescriptor) filterDescriptor, cellValue,
                            RadGridView.MasterTemplate.DataView.FilterEvaluate, row))
                        {
                            e.Visible = false;
                            return;
                        }
                    }
                    else if (!FilterEvaluateString(filterDescriptor, cellValue,
                        RadGridView.MasterTemplate.DataView.FilterEvaluate, row))
                    {
                        e.Visible = false;
                        return;
                    }
                }

                var nonStringFilterDescriptors = RadGridView.FilterDescriptors.Where(
                    x => !StringColumns.Contains(x.PropertyName));
                foreach (var filterDescriptor in nonStringFilterDescriptors)
                {
                    if (!RadGridView.MasterTemplate.DataView.FilterEvaluate(filterDescriptor, row))
                    {
                        e.Visible = false;
                        return;
                    }
                }
            }

            private static bool CompositeFilterEvaluateString(CompositeFilterDescriptor compositeFilterDescriptor,
                string cellValue, Func<FilterDescriptor, GridViewRowInfo, bool> gridFilterEvaluate, GridViewRowInfo row)
            {
                switch (compositeFilterDescriptor.LogicalOperator)
                {
                    case FilterLogicalOperator.And:
                        if (compositeFilterDescriptor.FilterDescriptors.Any(filterDescriptor =>
                        {
                            if (filterDescriptor.GetType() == typeof(CompositeFilterDescriptor))
                                return !CompositeFilterEvaluateString((CompositeFilterDescriptor) filterDescriptor,
                                    cellValue, gridFilterEvaluate, row);
                            return !FilterEvaluateString(filterDescriptor, cellValue, gridFilterEvaluate, row);
                        }))
                            return false;
                        break;
                    case FilterLogicalOperator.Or:
                        if (compositeFilterDescriptor.FilterDescriptors.All(filterDescriptor =>
                        {
                            if (filterDescriptor.GetType() == typeof(CompositeFilterDescriptor))
                                return !CompositeFilterEvaluateString((CompositeFilterDescriptor) filterDescriptor,
                                    cellValue, gridFilterEvaluate, row);
                            return !FilterEvaluateString(filterDescriptor, cellValue, gridFilterEvaluate, row);
                        }))
                            return false;
                        break;
                }
                return true;
            }

            private static bool FilterEvaluateString(FilterDescriptor filterDescriptor, string cellValue,
                Func<FilterDescriptor, GridViewRowInfo, bool> gridFilterEvaluate, GridViewRowInfo row)
            {
                var filterDescriptorValue = ((string) filterDescriptor.Value).ToLowerInvariant();
                switch (filterDescriptor.Operator)
                {
                    case FilterOperator.Contains:
                        if (CultureInfo.InvariantCulture.CompareInfo.IndexOf(cellValue, filterDescriptorValue,
                                CompareOptions.IgnoreNonSpace) == -1)
                            return false;
                        break;
                    case FilterOperator.NotContains:
                        if (CultureInfo.InvariantCulture.CompareInfo.IndexOf(cellValue, filterDescriptorValue,
                                CompareOptions.IgnoreNonSpace) != -1)
                            return false;
                        break;
                    case FilterOperator.StartsWith:
                        if (!CultureInfo.InvariantCulture.CompareInfo.IsPrefix(cellValue, filterDescriptorValue,
                            CompareOptions.IgnoreNonSpace))
                            return false;
                        break;
                    case FilterOperator.EndsWith:
                        if (!CultureInfo.InvariantCulture.CompareInfo.IsSuffix(cellValue, filterDescriptorValue,
                            CompareOptions.IgnoreNonSpace))
                            return false;
                        break;
                    case FilterOperator.IsEqualTo:
                        if (String.Compare(cellValue, filterDescriptorValue, CultureInfo.InvariantCulture,
                                CompareOptions.IgnoreNonSpace) != 0)
                            return false;
                        break;
                    case FilterOperator.IsNotEqualTo:
                        if (String.Compare(cellValue, filterDescriptorValue, CultureInfo.InvariantCulture,
                                CompareOptions.IgnoreNonSpace) == 0)
                            return false;
                        break;
                    default:
                        if (!gridFilterEvaluate.Invoke(filterDescriptor, row))
                            return false;
                        break;
                }
                return true;
            }
        }

        private static List<string> GetStringColumns(RadGridView radGridView)
        {
            var retVal = new List<string>();
            foreach (var column in radGridView.Columns)
            {
                if (column.DataType == typeof(string))
                {
                    retVal.Add(column.Name);
                }
            }
            return retVal;
        }

        /// <summary>
        /// Enables custom string filtering on <paramref name="radGridView"/>. It is case insensitive and
        /// tolerates differences in diacritical marks. For example, in a "equals" comparision, the value
        /// 'ëMúa' is treated as its equal to 'EmÜâ'.
        /// </summary>
        /// <param name="radGridView">Instance of <see cref="RadGridView"/> in which custom string filtering
        /// will be enabled.</param>
        public static void CustomStringFiltering(RadGridView radGridView)
        {
            var customFiltering = new CustomStringFilteringClass(radGridView);
            customFiltering.Enable();
        }
    }
}

用法很簡單：

RadGridViewHelper.CustomStringFiltering(radGridView);

其中radGridView是將更改字符串過濾行為的類RadGridView的實例。

我把它放在Q＆A風格的這里，這里鼓勵 ： 可以提出並回答你自己的問題 - Stack Overflow Blog

希望它能幫助並節省時間和頭痛給某人。