C# - 西宁威势电子信息服务有限公司

c# lamuda 表达式拼接

public static Expression<Func<T, bool>> Or<T>(this Expression<Func<T, bool>> expression1, Expression<Func<T, bool>> expression2) { var invokedExpression = Expression.Invoke(expression2, expression1.Parameters.Cast<Expression>()); return Expression.Lambda<Func<T, bool>>(Expression.Or(expression1.Body, invokedExpression), expression1.Parameters); } public static Expression<Func<T, bool>> And<T>(this Express ...

905 次

2022/8/31

C# SqlHelper

using System;using System.Data;using System.Xml;using System.Data.SqlClient;using System.Collections;using System.Configuration;using WinDPAPI;using System.Text;//如果要获取连接数据连接对象或字符串的话，先要修改SQLHelper类中GetConnSting() 方法中的ConfigurationManager.ConnectionStrings["ConStr"].ConnectionString;才能调用。namespace DAL{ /// <summary> /// SqlServer数据访问帮助类 /// </summary> public sealed class SqlHelper { #region ...

1243 次

2022/8/31

DbHelper

using System;using System.Configuration;using System.Data;using System.Data.Common;using System.Data.OleDb;using System.Data.SqlClient;namespace DB{ /// <summary> /// 数据库助手类 /// </summary> public class DbHelper { private static string dbProviderName = ConfigurationManager.AppSettings["providerName"]; private static string dbConnectionString = ConfigurationManager.AppSettings["connectionString"]; private D ...

1219 次

2022/8/31