From bcc00305ab59b39afce52eab13139f8546142147 Mon Sep 17 00:00:00 2001
From: NEVERMINDY <17321086315@163.com>
Date: Sun, 16 Oct 2022 12:45:49 +0800
Subject: [PATCH] Add amount limit to "Transfers" component

---
 .../Components/Transfer/Transfer.razor.cs     | 51 +++++++++++++++++++
 src/BootstrapBlazor/Locales/zh.json           |  4 +-
 2 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/src/BootstrapBlazor/Components/Transfer/Transfer.razor.cs b/src/BootstrapBlazor/Components/Transfer/Transfer.razor.cs
index cae2d43a3..9844c6ab1 100644
--- a/src/BootstrapBlazor/Components/Transfer/Transfer.razor.cs
+++ b/src/BootstrapBlazor/Components/Transfer/Transfer.razor.cs
@@ -104,6 +104,32 @@ public partial class Transfer<TValue>
     [Parameter]
     public string? RightPannelSearchPlaceHolderString { get; set; }
 
+    /// <summary>
+    /// 获得/设置 右侧面板包含的最大数量, 默认为 0 不限制
+    /// </summary>
+    [Parameter]
+    public int Max { get; set; }
+
+    /// <summary>
+    /// 获得/设置 设置最大值时错误消息文字
+    /// </summary>
+    [Parameter]
+    [NotNull]
+    public string? MaxErrorMessage { get; set; }
+
+    /// <summary>
+    /// 获得/设置 右侧面板包含的最大数量，默认为 0 不限制
+    /// </summary>
+    [Parameter]
+    public int Min { get; set; }
+
+    /// <summary>
+    /// 获得/设置 设置最小值时错误消息文字
+    /// </summary>
+    [Parameter]
+    [NotNull]
+    public string? MinErrorMessage { get; set; }
+
     /// <summary>
     /// 获得/设置 数据样式回调方法 默认为 null
     /// </summary>
@@ -154,6 +180,8 @@ public partial class Transfer<TValue>
 
         LeftPanelText ??= Localizer[nameof(LeftPanelText)];
         RightPanelText ??= Localizer[nameof(RightPanelText)];
+        MinErrorMessage ??= Localizer[nameof(MinErrorMessage)];
+        MaxErrorMessage ??= Localizer[nameof(MaxErrorMessage)];
 
         var list = CurrentValueAsString.Split(',', StringSplitOptions.RemoveEmptyEntries);
         LeftItems.Clear();
@@ -174,6 +202,16 @@ public partial class Transfer<TValue>
                 RightItems.Add(item);
             }
         }
+
+        if (Min > 0)
+        {
+            Rules.Add(new MinValidator() { Value = Min, ErrorMessage = MinErrorMessage });
+        }
+        if (Max > 0)
+        {
+            Rules.Add(new MaxValidator() { Value = Max, ErrorMessage = MaxErrorMessage });
+        }
+
     }
 
     /// <summary>
@@ -202,6 +240,19 @@ public partial class Transfer<TValue>
                 await OnSelectedItemsChanged(isLeft ? target : source);
             }
         }
+
+
+        if (Min > 0 || Max > 0)
+        {
+            var validationContext = new ValidationContext(Value!) { MemberName = FieldIdentifier?.FieldName };
+            var validationResults = new List<ValidationResult>();
+
+            await ValidatePropertyAsync(RightItems, validationContext, validationResults);
+            ToggleMessage(validationResults, true);
+        }
+
+        StateHasChanged();
+
     }
 
     /// <summary>
diff --git a/src/BootstrapBlazor/Locales/zh.json b/src/BootstrapBlazor/Locales/zh.json
index fd08ecffd..9e652ff90 100644
--- a/src/BootstrapBlazor/Locales/zh.json
+++ b/src/BootstrapBlazor/Locales/zh.json
@@ -283,7 +283,9 @@
   },
   "BootstrapBlazor.Components.Transfer": {
     "LeftPanelText": "全部",
-    "RightPanelText": "已选"
+    "RightPanelText": "已选",
+    "MinErrorMessage": "最少请选择{0}项",
+    "MaxErrorMessage": "最多可选择{0}项"
   },
   "BootstrapBlazor.Components.TransferPanel": {
     "SearchPlaceHolderString": "请输入 ...",
-- 
Gitee