添加全局转换实体属性名方法

FreeSql/Internal/StringConvertType.cs

@@ -0,0 +1,45 @@
+namespace FreeSql.Internal
+{
+    public enum StringConvertType
+    {
+        /// <summary>
+        /// 不进行任何处理
+        /// </summary>
+        None = 0,
+
+        /// <summary>
+        /// 将帕斯卡命名字符串转换为下划线分隔字符串
+        /// <para></para>
+        /// BigApple -> Big_Apple
+        /// </summary>
+        PascalCaseToUnderscore,
+
+        /// <summary>
+        /// 将帕斯卡命名字符串转换为下划线分隔字符串，且转换为全大写
+        /// <para></para>
+        /// BigApple -> BIG_APPLE
+        /// </summary>
+        PascalCaseToUnderscoreWithUpper,
+
+        /// <summary>
+        /// 将帕斯卡命名字符串转换为下划线分隔字符串，且转换为全小写
+        /// <para></para>
+        /// BigApple -> big_apple
+        /// </summary>
+        PascalCaseToUnderscoreWithLower,
+
+        /// <summary>
+        /// 将字符串转换为大写
+        /// <para></para>
+        /// BigApple -> BIGAPPLE
+        /// </summary>
+        Upper,
+
+        /// <summary>
+        /// 将字符串转换为小写
+        /// <para></para>
+        /// BigApple -> bigapple
+        /// </summary>
+        Lower
+    }
+}

FreeSql/Internal/StringUtils.cs

@@ -0,0 +1,20 @@
+using System.Linq;
+
+namespace FreeSql.Internal
+{
+    public static class StringUtils
+    {
+        /// <summary>
+        /// 将帕斯卡命名字符串转换为下划线分隔字符串
+        /// <para></para>
+        /// BigApple -> Big_Apple
+        /// </summary>
+        /// <param name="str"></param>
+        /// <returns></returns>
+        public static string PascalCaseToUnderScore(string str)
+        {
+            return string.Concat(str.Select((x, i) =>
+                i > 0 && char.IsUpper(x) ? "_" + x.ToString() : x.ToString()));
+        }
+    }
+}