refactor autocomplete to be flexible and reusable

src/AutoCrudAdmin/Controllers/AutoCrudAdminController.cs

@@ -219,6 +219,7 @@ public override void OnActionExecuting(ActionExecutingContext context)
     /// <param name="searchProperty">The property to search.</param>
     /// <returns>The autocomplete results.</returns>
     [HttpGet]
+    [Obsolete]
     public virtual IEnumerable<DropDownViewModel> Autocomplete([FromQuery] string searchTerm, string searchProperty)
     {
         var entityType = typeof(TEntity);
@@ -244,6 +245,38 @@ public virtual IEnumerable<DropDownViewModel> Autocomplete([FromQuery] string se
         return entities;
     }
 
+    /// <summary>
+    /// Handles autocomplete extended searches.
+    /// </summary>
+    /// <param name="searchTerm">The search term.</param>
+    /// <param name="searchProperty">The property to search is configured by FormControlViewModel.</param>
+    /// <param name="maxResults">The max autocomplete result is configured by FormControlViewModel.</param>
+    /// <returns>The autocomplete results.</returns>
+    [HttpGet]
+    public IEnumerable<DropDownViewModel> AutocompleteExtended(
+                [FromQuery] string searchTerm,
+                string searchProperty,
+                int maxResults)
+    {
+        if (string.IsNullOrWhiteSpace(searchProperty))
+        {
+            throw new ArgumentException("No search property added!");
+        }
+
+        var entityType = typeof(TEntity);
+        var searchedProperty = entityType.GetProperty(searchProperty);
+
+        var keys = entityType.GetPrimaryKeyPropertyInfos();
+
+        if (searchedProperty == null || !keys.Any())
+        {
+            throw new ArgumentException("No such property exists on the entity!");
+        }
+
+        var containsExpression = ExpressionsBuilder.ForGetPropertyContains<TEntity>(searchedProperty, searchTerm);
+        return this.FilterAutocompleteResults(maxResults, searchedProperty, keys, containsExpression);
+    }
+
     /// <summary>
     /// Shows the index view. Contains a grid with paging, sorting and filtering.
     /// </summary>
@@ -720,7 +753,7 @@ protected IActionResult RedirectToActionWithStringFilter(
             actionName,
             gridStringFilterType.ToString());
 
-     /// <summary>
+    /// <summary>
     /// Builds custom grid columns.
     /// </summary>
     /// <param name="columns">Page columns.</param>
@@ -836,6 +869,23 @@ private static void CopyFormPropertiesToExistingEntityFromNewEntity(TEntity exis
             .ToList()
             .ForEach(property => property.SetValue(existingEntity, property.GetValue(newEntity, null), null));
 
+    private IEnumerable<DropDownViewModel> FilterAutocompleteResults(int maxResults, PropertyInfo searchedProperty, IEnumerable<PropertyInfo> keys, Expression<Func<TEntity, bool>> expression)
+    {
+        var entities = this.Set
+            .AsNoTracking()
+            .Where(expression)
+            .Take(maxResults)
+            .ToList();
+
+        return entities
+            .Select(x => new DropDownViewModel
+            {
+                Value = keys.Select(k => k.GetValue(x) !.ToString()),
+                Name = searchedProperty.GetValue(x) !.ToString() !,
+            })
+            .ToList();
+    }
+
     private IHtmlGrid<TEntity> GenerateGrid(IHtmlHelper<AutoCrudAdminIndexViewModel> htmlHelper)
         => htmlHelper
             .Grid(this.GetQueryWithIncludes(this.MasterGridFilter))

src/AutoCrudAdmin/Enumerations/FormControlType.cs

@@ -29,4 +29,9 @@ public enum FormControlType
     /// Represents an autocomplete control, where the user's input is completed automatically as they type.
     /// </summary>
     Autocomplete = 4,
+
+    /// <summary>
+    /// Represents an autocomplete control, where the user's input is completed automatically as they type. Extended to work with more then just strings and configure results received.
+    /// </summary>
+    AutocompleteExtended = 5,
 }

src/AutoCrudAdmin/Extensions/TypeExtensions.cs

@@ -149,6 +149,18 @@ public static bool IsNavigationProperty(this Type type)
     public static bool IsEnumerableExceptString(this Type type)
         => typeof(IEnumerable).IsAssignableFrom(type) && type != typeof(string);
 
+    /// <summary>
+    /// This method returns the MethodInfo object for the ToString method of the Object class.
+    /// </summary>
+    /// <returns>Returns MethodInfo? (object.ToString()).</returns>
+    public static MethodInfo? GetObjectToStringMethodInfo() => typeof(object).GetMethod(nameof(string.ToString));
+
+    /// <summary>
+    /// This method returns the MethodInfo object for the Contains method of the String class.
+    /// </summary>
+    /// <returns>Returns MethodInfo? (string.Contains()).</returns>
+    public static MethodInfo? GetStringContainsMethodInfo() => typeof(string).GetMethod(nameof(string.Contains), new[] { typeof(string) });
+
     private static DbContext? CreateDbContext(Type type)
     {
         try

src/AutoCrudAdmin/Helpers/ExpressionsBuilder.cs

@@ -112,6 +112,42 @@ public static Func<TEntity, object> ForGetPropertyValue<TEntity>(PropertyInfo pr
             instanceParam).Compile();
     }
 
+    /// <summary>
+    /// Constructs a method for getting values that contains specific search term.
+    /// </summary>
+    /// <typeparam name="TEntity">The type of the entity.</typeparam>
+    /// <param name="property">The property for which we construct the method.</param>
+    /// <param name="searchTerm">The search term.</param>
+    /// <returns>All matching obejects.</returns>
+    public static Expression<Func<TEntity, bool>> ForGetPropertyContains<TEntity>(PropertyInfo property, string searchTerm)
+    {
+        var entityType = typeof(TEntity);
+        var parameter = Expression.Parameter(entityType, "model");
+
+        var propertyAccess = Expression.Property(parameter, property);
+        var searchTermExpression = Expression.Constant(searchTerm, typeof(string));
+
+        var containsMethod = Extensions.TypeExtensions.GetStringContainsMethodInfo();
+
+        if (property.PropertyType == typeof(string))
+        {
+            // model.Property.Contains(searchTerm)
+            var containsCall = Expression.Call(propertyAccess, containsMethod !, searchTermExpression);
+
+            // model => model.Property.Contains(searchTerm)
+            return Expression.Lambda<Func<TEntity, bool>>(containsCall, parameter);
+        }
+
+        // If the property type is not string, convert it to string and then use Contains method
+        var toStringMethod = Extensions.TypeExtensions.GetObjectToStringMethodInfo();
+
+        MethodCallExpression? toStringCall = null;
+        toStringCall = Expression.Call(propertyAccess, toStringMethod !);
+
+        var body = Expression.Call(toStringCall, containsMethod !, searchTermExpression);
+        return Expression.Lambda<Func<TEntity, bool>>(body, parameter);
+    }
+
     private static Expression ForPrimaryKeySubExpression(
         string name,
         string value,

src/AutoCrudAdmin/TagHelpers/FormInputTagHelper.cs

@@ -138,7 +138,7 @@ public override Task ProcessAsync(TagHelperContext context, TagHelperOutput outp
         {
             this.PrepareExpandableMultiChoiceCheckBox(output);
         }
-        else if (this.FormControlType == FormControlType.Autocomplete)
+        else if (this.FormControlType == FormControlType.Autocomplete || this.FormControlType == FormControlType.AutocompleteExtended)
         {
             this.PrepareAutocompleteDropdown(output);
         }

src/AutoCrudAdmin/ViewModels/FormControlViewModel.cs

@@ -82,4 +82,14 @@ public string DisplayName
     /// Gets or sets the entity id for the autocomplete feature of the form control.
     /// </summary>
     public string? FormControlAutocompleteEntityId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the entity property that autocomplete will search by. (Autocomplete Extended).
+    /// </summary>
+    public string? SearchByPropertyAutocompleteConfiguration { get; set; }
+
+    /// <summary>
+    /// Gets or sets how much autocomplete results will be shown (20 by default). (Autocomplete Extended).
+    /// </summary>
+    public int NumberOfAutocompleteItemsShownConfiguration { get; set; } = 20;
 }

src/AutoCrudAdmin/Views/Shared/Autocomplete/_AutocompleteExtendedPartial.cshtml

@@ -0,0 +1,44 @@
+@model AutoCrudAdmin.ViewModels.FormControlViewModel
+
+@{
+    var controllerName = Model.FormControlAutocompleteController;
+}
+
+@Html.Hidden("AutocompleteId", "#" + Model.Name + "Id")
+@Html.Hidden("ControllerName", controllerName)
+@Html.Hidden(Model.FormControlAutocompleteEntityId, "")
+
+<script type="text/javascript">
+    $(function () {
+        const autocompleteId = $('#AutocompleteId').val();
+        const controllerName = $('#ControllerName').val();
+        const hiddenId = '@Model.FormControlAutocompleteEntityId';
+
+        $(autocompleteId).autocomplete({
+            source: function (request, response) {
+                $.ajax({
+                    type: "GET",
+                    url: `/${controllerName}/AutocompleteExtended`,
+                    data: {
+                        searchTerm: request.term,
+                        searchProperty: '@Model.SearchByPropertyAutocompleteConfiguration',
+                        maxResults: @Model.NumberOfAutocompleteItemsShownConfiguration,
+                    },
+                    success: function (data) {
+                        response($.map(data, function (item) {
+                            return { label: item.name, value: item.value };
+                        }));
+                    },
+                    error: function (error) {
+                        console.log(error);
+                    },
+                });
+            },
+            select: function (event, ui) {
+                event.preventDefault();
+                $(`#${hiddenId}`).val(ui.item.value);
+                $(autocompleteId).val(ui.item.label);
+            },
+        });
+    });
+</script>

src/AutoCrudAdmin/Views/Shared/Autocomplete/_AutocompletePartial.cshtml

@@ -0,0 +1,42 @@
+@model AutoCrudAdmin.ViewModels.FormControlViewModel
+
+@{
+    var controllerName = Model.FormControlAutocompleteController;
+}
+
+@Html.Hidden("AutocompleteId", "#" + Model.Name + "Id")
+@Html.Hidden("ControllerName", controllerName)
+@Html.Hidden(Model.FormControlAutocompleteEntityId, "")
+
+<script type="text/javascript">
+    $(function () {
+        const autocompleteId = $('#AutocompleteId').val();
+        const controllerName = $('#ControllerName').val();
+        const hiddenId = '@Model.FormControlAutocompleteEntityId';
+
+        $(autocompleteId).autocomplete({
+            source: function (request, response) {
+                $.ajax({
+                    type: "GET",
+                    url: `/${controllerName}/Autocomplete`,
+                    data: {
+                        searchTerm: request.term
+                    },
+                    success: function (data) {
+                        response($.map(data, function (item) {
+                            return { label: item.name, value: item.value };
+                        }));
+                    },
+                    error: function (error) {
+                        console.log(error);
+                    },
+                });
+            },
+            select: function (event, ui) {
+                event.preventDefault();
+                $(`#${hiddenId}`).val(ui.item.value);
+                $(autocompleteId).val(ui.item.label);
+            },
+        });
+    });
+</script>

src/AutoCrudAdmin/Views/Shared/_EnityFormControlsPartial.cshtml

@@ -56,44 +56,11 @@
 
     if (formControl.FormControlType == FormControlType.Autocomplete)
     {
-        @Html.Hidden("AutocompleteId", "#" + formControl.Name + "Id")
-        var controllerName = formControl.FormControlAutocompleteController;
-        @Html.Hidden("ControllerName", controllerName)
-        @Html.Hidden(formControl.FormControlAutocompleteEntityId, "")
-
-        <script type="text/javascript">
-           $(function() {
-               const autocompleteId= $('#AutocompleteId').val();
-               const controllerName = $('#ControllerName').val();
-               const hiddenId = '@formControl.FormControlAutocompleteEntityId';
-
-             $(autocompleteId).autocomplete({
-               source: function(request, response) {
-                 $.ajax({
-                   type: "GET",
-
-                   url: `/${controllerName}/Autocomplete`,
-                   data: { 
-                     searchTerm: request.term
-                   },
-                   success: function (data) {
-                         response($.map(data, function (item) {
-                             return { label: item.name, value: item.value };
-                         }));
-                     },
-                   error: function(error){
-                       console.log(error);
-                    },
-                  });
-                 },
-               select: function(event, ui) {
-                    event.preventDefault();
-                    $(`#${hiddenId}`).val(ui.item.value);
-                    $(autocompleteId).val(ui.item.label);
-                   },
-               });
-           });
-        </script>
+        @await Html.PartialAsync("Autocomplete/_AutocompletePartial", formControl);
+    }
+    else if (formControl.FormControlType == FormControlType.AutocompleteExtended)
+    {
+        @await Html.PartialAsync("Autocomplete/_AutocompleteExtendedPartial", formControl);
     }
 }