自定义属性

属性定义

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[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)] public class ColumnNameAttribute : Attribute {     private string _columnName;     public ColumnNameAttribute(string columnName, string columnChsName=null)     {         this._columnName = columnName;         this._columnChsName = columnChsName;     }       public string ColumnName     {         get { return _columnName; }     }       private string _columnChsName;       public string ColumnChsName     {         get { return _columnChsName; }     } }

　　属性使用

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var properties = typeof(T).GetProperties().Where(v => v.IsDefined(typeof(ColumnNameAttribute), true)).ToList();    foreach (var pro in properties)             {                 var sourctValue = GetString(pro.GetValue(sourceObj, null));                 var newValue = GetString(pro.GetValue(newObj, null));                 if (sourctValue != newValue)                 {                     string colName = ((ColumnNameAttribute)pro.GetCustomAttributes(typeof(ColumnNameAttribute), true)[0]).ColumnChsName;                     logContent.AppendLine("</br>" + colName + ":从" + sourctValue + " 变更到 " + newValue);                     hasChanged = true;                 }             }

　　私有方法

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private static string GetString(object o) {     if (o == null || o== DBNull.Value)     {         return string.Empty;     }     else     {         return o.ToString();     } }