linq查询条件参数化--解决实际问题记录

前置条件

单位批量加解密方法脱离世纪，太难用了。返回字典。并且限制每次批量100.

实际使用中一般都是实体类集合中的某一个或某几个字段需要解密。

基于以上原因原有的无法满足需求，重新封装。

使用linq+反射完成。其中linq查询条件参数化实际上就是委托。

代码如下：

/// <summary>
/// 转换实体集合
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="list">需要转换的集合</param>
/// <param name="selector">需要解密的字段</param>
/// <param name="propertyGet">解密字段</param>
/// <param name="propertySet">解密后的值需赋值的字段</param>
/// <returns>返回解密后的实体集合</returns>
public static List<T> DecryptByModels<T>(IEnumerable<T> list, Func<T, string> selector, string propertyGet, string propertySet) where T : new()
{
var myList = list.ToList();
var dictionary = SecurityHelper.Decrypt<T>(myList, selector);

int len = myList.Count();

for (int i = 0; i < len; i++)
{
myList[i] = SecurityHelper.SetPropertyValue<T>(myList[i], propertyGet, propertySet, dictionary);
}
return myList;
}

/// <summary>
/// 实体集合传入需要解密字段，并返回批量解密数据
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="source"></param>
/// <param name="selector"></param>
/// <returns></returns>
private static Dictionary<string, string> Decrypt<T>(this IEnumerable<T> source, Func<T, string> selector) where T : new()
{
var result = source.Select(selector).Where(p => !string.IsNullOrWhiteSpace(p)).Distinct().ToList();

int cutNum = (result.Count / 100) + ((result.Count % 100) > 0 ? 1 : 0);
Dictionary<string, string> dictionary = new Dictionary<string, string>();
for (int i = 0; i < cutNum; i++)
{
var dictionaryBatch = SecurityHelper.DecryptBatch(result.Skip(i * 100).Take(100).ToList());
dictionary = dictionary.Concat(dictionaryBatch).ToDictionary(p => p.Key, p => p.Value);
}
return dictionary;
}

/// <summary>
/// 集合解密后数据赋值
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="t"></param>
/// <param name="getProperty"></param>
/// <param name="setProperty"></param>
/// <param name="dictionary"></param>
/// <returns></returns>
private static T SetPropertyValue<T>(T t, string getProperty, string setProperty, Dictionary<string, string> dictionary)
{
PropertyInfo getPropertyInfo = t.GetType().GetProperty(getProperty);
PropertyInfo setPropertyInfo = t.GetType().GetProperty(setProperty);
var getValue = getPropertyInfo.GetValue(t, null);
//为空不赋值了
if (getValue == null || string.IsNullOrWhiteSpace(getValue.ToString()))
{
return t;
}
var result = dictionary.Where(p => p.Key == getPropertyInfo.GetValue(t, null).ToString()).Select(p => p.Value).ToList();
string value = result.Count > 0 ? result.First() : "";
setPropertyInfo.SetValue(t, value);
return t;
}

调用方式

List<Test> list = new List<Test>();
list.Add(new Test() { a1 = "E8637AE9A790EA36A8E2353B178BED159099DD8FBD5EA5EBBFDEAF70809425F2" });
list.Add(new Test() { a1 = "71A094E8F88DBF5F21CCA394DBE094E4971050E8A935BEB2AC26875FA0F541D8" });

list = SecurityHelper.DecryptByModels(list, p => p.a1, "a1", "a2");

public class Test
{
public string a1 { get; set; }
public string a2 { get; set; }

}