init

AspDotNetCore2BinderFloatingDecimalModel.csproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.2</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.Core" Version="2.2.5" />
+  </ItemGroup>
+
+</Project>

CustomDoubleModelBinderProvider.cs

@@ -0,0 +1,33 @@
+////////////////////////////////////////////////
+// © https://github.com/badhitman - @fakegov
+////////////////////////////////////////////////
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Binders;
+using Microsoft.Extensions.Logging;
+
+namespace AspDotNetCore2BinderFloatingDecimalModel
+{
+    public class CustomDecimalModelBinderProvider : IModelBinderProvider
+    {
+        private IModelBinder binder;
+
+        public IModelBinder GetBinder(ModelBinderProviderContext context)
+        {
+            ILoggerFactory logger = context.Services.GetService(typeof(ILoggerFactory)) as ILoggerFactory;
+
+            if (context.Metadata.ModelType == typeof(double))
+                binder = new CustomFloatingModelBinder(new SimpleTypeModelBinder(typeof(double), logger));
+
+            else if (context.Metadata.ModelType == typeof(float))
+                binder = new CustomFloatingModelBinder(new SimpleTypeModelBinder(typeof(float), logger));
+
+            else if (context.Metadata.ModelType == typeof(decimal))
+                binder = new CustomFloatingModelBinder(new SimpleTypeModelBinder(typeof(decimal), logger));
+
+            else
+                return null;
+
+            return binder;
+        }
+    }
+}

CustomFloatingModelBinder.cs

@@ -0,0 +1,104 @@
+////////////////////////////////////////////////
+// © https://github.com/badhitman - @fakegov
+////////////////////////////////////////////////
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+using System;
+using System.Globalization;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+
+namespace AspDotNetCore2BinderFloatingDecimalModel
+{
+    public class CustomFloatingModelBinder : IModelBinder
+    {
+        private readonly IModelBinder FallbackModelBinder;
+        private string FieldName;
+        private string FieldValueAsString;
+        private string FieldValueAsNormalString;
+        private ValueProviderResult PartValues;
+
+        protected readonly Regex FloatPattern = new Regex(@"^(-?)[0-9]*(?:[.,][0-9]*)?$", RegexOptions.Compiled);
+        protected readonly Regex FloatSeparator = new Regex(@"[.,]", RegexOptions.Compiled);
+
+        public CustomFloatingModelBinder(IModelBinder fallback_model_binder)
+        {
+            this.FallbackModelBinder = fallback_model_binder;
+        }
+
+        public Task BindModelAsync(ModelBindingContext model_binding_context)
+        {
+            if (model_binding_context == null)
+                throw new ArgumentNullException(nameof(model_binding_context));
+
+            FieldName = model_binding_context.FieldName;
+
+            PartValues = model_binding_context.ValueProvider.GetValue(FieldName);
+
+            if (PartValues == ValueProviderResult.None)
+                return FallbackModelBinder.BindModelAsync(model_binding_context);
+
+            FieldValueAsString = FieldValueAsNormalString = PartValues.FirstValue;
+
+            ////////////////////////////////////////////////////
+            // если строка содержит десятичный/дробный разделитель -> строка дополняется нулями с обоих сторон.
+            // Таким образом исключаем точки в начале или в конце строки:
+            // ".5" -> "0.50"
+            // "5." -> "05.0"
+            if (FloatSeparator.IsMatch(FieldValueAsNormalString))
+                FieldValueAsNormalString = "0" + FieldValueAsNormalString + "0";
+
+            ////////////////////////////////////////////////////
+            // заменим дробный разделитель на текущий системный
+            FieldValueAsNormalString = FloatSeparator.Replace(FieldValueAsNormalString, CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator);
+
+            ////////////////////////////////////////////////////
+            // если не корректная строка -> передаём привязку системному привязчику
+            if (!FloatPattern.IsMatch(FieldValueAsNormalString))
+                return FallbackModelBinder.BindModelAsync(model_binding_context);
+
+            if (model_binding_context.ModelMetadata.ModelType == typeof(double))
+                model_binding_context.Result = ModelBindingResult.Success(GetDoubleFromString);
+            else if (model_binding_context.ModelMetadata.ModelType == typeof(float))
+                model_binding_context.Result = ModelBindingResult.Success(GetFloatFromString);
+            else if (model_binding_context.ModelMetadata.ModelType == typeof(decimal))
+                model_binding_context.Result = ModelBindingResult.Success(GetDecimalFromString);
+            else
+                return FallbackModelBinder.BindModelAsync(model_binding_context);
+
+            return Task.CompletedTask;
+        }
+
+        public double GetDoubleFromString
+        {
+            get
+            {
+                if (!double.TryParse(FieldValueAsNormalString, NumberStyles.AllowDecimalPoint, CultureInfo.CurrentCulture, out double ret_val))
+                    return 0;
+
+                return ret_val;
+            }
+        }
+
+        public decimal GetDecimalFromString
+        {
+            get
+            {
+                if (!decimal.TryParse(FieldValueAsNormalString, NumberStyles.AllowDecimalPoint, CultureInfo.CurrentCulture, out decimal ret_val))
+                    return 0;
+
+                return ret_val;
+            }
+        }
+
+        public float GetFloatFromString
+        {
+            get
+            {
+                if (!float.TryParse(FieldValueAsNormalString, NumberStyles.AllowDecimalPoint, CultureInfo.CurrentCulture, out float ret_val))
+                    return 0;
+
+                return ret_val;
+            }
+        }
+    }
+}

README.md

@@ -1,2 +1,16 @@
 # ASP.NET Core 2.2 BinderFloatingDecimalModel
 Привязчик модели для числовых значений double, float и decimal в ASP.NET Core 2.2
+
+Использование:
+```C#
+using AspDotNetCore2BinderFloatingDecimalModel;
+// ...
+public void ConfigureServices(IServiceCollection services)
+{
+	// ...
+	services.AddMvc(opts =>
+	{
+		opts.ModelBinderProviders.Insert(0, new CustomDecimalModelBinderProvider());
+	}).SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
+}
+```