不使用表达式树，使用强类型生成where子句，好处是性能高，相比表达式树生成的sql，10倍+
目前只支持生成where条件、查询语句，后期会增加生成Update SQL
支持生成Sqlserver、Mysql语句
where子句支持相等、比较大小、Between、Like、In操作
sql语句支持设置select字段、top、order by；不支持联表查询、group by
客户端调用：
public static void Main(string[] args) { var sqlBuilder = new SqlBuilder(typeof(Person)); //生成查询SQL #region 单个条件查询#SELECT * FROM `Person` WHERE `ID`=1 LIMIT 10 var filter = new EqualFieldFilter<int>("ID", 1); var sql = sqlBuilder .SetTop(10) .SetWhere(filter) .BuildSelectSql(); #endregion #region 复杂条件查询#SELECT `ID`,`Name` FROM `Person` WHERE ((`ID`=1 AND (`Age`=13 OR `Name`=1 OR `name` LIKE 'fan%'))) LIMIT 10 var filter2 = new AndFieldFilter(new EqualFieldFilter<int>("ID", 1), new OrFieldFilter(new EqualFieldFilter<int>("Age", 13), new EqualFieldFilter<int>("Name", 1), new LikeFieldFilter("name", "fan", LikeMode.Start))); var sql2 = sqlBuilder .SetTableName(nameof(Person)) .SetAndWhere(filter2) .BuildSelectSql(); #endregion #region 指定SELECT字段查询#SELECT `ID`,`Name` FROM `Person` WHERE LIMIT 10 var sql3 = sqlBuilder .SetTableName(nameof(Person)) .SetSelect(nameof(Person.ID), nameof(Person.Name)) .BuildSelectSql(); sql3 = sqlBuilder .SetTableName(nameof(Person)) .SetWhere(null) .SetSelect(nameof(Person.ID), nameof(Person.Name)) .BuildSelectSql(); #endregion #region 带排序查询#SELECT `ID`,`Name` FROM `Person` WHERE (`ID`=1) ORDER BY ID ASC,Name DESC LIMIT 10 var sql4 = sqlBuilder .SetTableName(nameof(Person)) .SetAndWhere(filter) .SetOrderBy(new Dictionary<string, int> { { "ID", 1 }, { "Name", -1 } }) .BuildSelectSql(); #endregion //生成WhereSQL #region 生成AndWhere#(`ID`=1 AND `Age`>13 AND `Name` LIKE 'fan%') var filter4 = new FieldFilter[] { new EqualFieldFilter<int>(nameof(Person.ID), 1), new CompareFieldFilter<int>(nameof(Person.Age), 13, ">"), new LikeFieldFilter(nameof(Person.Name), "fan", LikeMode.Start) }; var whereSql1 = SqlBuilder.BuildAndWhere(filter4); //使用Dictionary类型参数 whereSql1 = SqlBuilder.BuildAndWhere(new Dictionary<string, object> { { "ID", 1 }, { "Birthday", DateTime.Now }, { "Name", "fan" } }); #endregion #region 生成OrWhere#(`ID`=1 OR `Age`>13 OR `Name` LIKE 'fan%') var whereSql2 = SqlBuilder.BuildOrWhere(filter4); #endregion #region 生成复杂Where(`ID` = 1 AND (`Age` = 13 OR `name` LIKE 'fan%')) var filter5 = new AndFieldFilter(new EqualFieldFilter<int>("ID", 1), new OrFieldFilter(new EqualFieldFilter<int>("Age", 13), new LikeFieldFilter("name", "fan", LikeMode.Start))); var whereSql3 = SqlBuilder.BuildWhere(filter5); #endregion Console.ReadKey(); }
实体类：
public class Person { public int ID { get; set; } public string StudentNumber { get; set; } public int Age { get; set; } public string Name { get; set; } public string ClassName { get; set; } }
SqlBuilder：
public class SqlBuilder { public static readonly ESqlDataType SQL_DATA_TYPE = ESqlDataType.MySql;//如果要切换数据库，只需要改此处 public static readonly string START_OPE = "`"; public static readonly string END_OPE = "`"; private static readonly ConcurrentDictionary<Type, PropertyInfo[]> TYPE_CACHE = new ConcurrentDictionary<Type, PropertyInfo[]>(); private static readonly ConcurrentDictionary<Type, string> EXPRESSION_CACHE = new ConcurrentDictionary<Type, string>(); private const string SQLSERVER_FORMAT = "SELECT {top} {select} FROM {table} {where} {orderby}"; private const string MYSQL_FORMAT = "SELECT {select} FROM {table} {where} {orderby} {top}"; private string _selectSql = " * "; private string _tableName = string.Empty; private string _topSql = string.Empty; private string _orderBySql = string.Empty; private WherePart _wherePart = null; #region Constructor static SqlBuilder() { if (SQL_DATA_TYPE == ESqlDataType.SqlServer) { START_OPE = "["; END_OPE = "]"; } } public SqlBuilder() { } public SqlBuilder(string tableName) { this.SetTableName(tableName); } public SqlBuilder(Type tableType) { this.SetTableName(tableType.Name); } #endregion #region BuildSql public WherePart BuildSelectSql() { string sql = (SQL_DATA_TYPE == ESqlDataType.MySql ? MYSQL_FORMAT : SQLSERVER_FORMAT); if (string.IsNullOrWhiteSpace(this._tableName)) { throw new ArgumentException("Invoke SetTableName Method"); } sql = sql.Replace("{table}", this._tableName); sql = sql.Replace("{select}", this._selectSql); sql = sql.Replace("{where}", this._wherePart != null ? this._wherePart.Sql : string.Empty); sql = sql.Replace("{top}", this._topSql); sql = sql.Replace("{orderby}", this._orderBySql); return new WherePart(sql, this._wherePart?.Parameters); } #endregion #region BuildWhereSql /// <summary> /// 创建where（AND） /// </summary> /// <param name="FieldFilters"></param> /// <returns></returns> public static WherePart BuildAndWhere(params FieldFilter[] FieldFilters) { string sql = string.Empty; Dictionary<string, object> parameters = new Dictionary<string, object>(); if (FieldFilters?.Length > 0) { sql = new AndFieldFilter(FieldFilters).BuildCriteria(out string where, parameters) ? where : string.Empty; } return new WherePart(sql, parameters); } /// <summary> /// 创建where（AND） /// </summary> /// <param name="pairs"></param> /// <returns></returns> public static WherePart BuildAndWhere(ICollection<KeyValuePair<string, object>> pairs) { WherePart wherePart = null; Dictionary<string, object> parameters = new Dictionary<string, object>(); if (pairs?.Count > 0) { wherePart = SqlBuilder.BuildAndWhere(BuildFildFilters(pairs)); } return wherePart; } /// <summary> /// 创建where（OR） /// </summary> /// <param name="FieldFilters"></param> /// <returns></returns> public static WherePart BuildOrWhere(params FieldFilter[] FieldFilters) { WherePart wherePart = null; Dictionary<string, object> parameters = new Dictionary<string, object>(); if (FieldFilters?.Length > 0) { if (new OrFieldFilter(FieldFilters).BuildCriteria(out string where, parameters)) { wherePart = new WherePart(where, parameters); } } return wherePart; } /// <summary> /// 创建where（OR） /// </summary> /// <param name="pairs"></param> /// <returns></returns> public static WherePart BuildOrWhere(ICollection<KeyValuePair<string, object>> pairs) { WherePart wherePart = null; if (pairs?.Count > 0) { wherePart = SqlBuilder.BuildOrWhere(BuildFildFilters(pairs)); } return wherePart; } /// <summary> /// 创建复杂where sql /// </summary> /// <param name="complexFieldFilter"></param> /// <returns></returns> public static WherePart BuildWhere(FieldFilter complexFieldFilter) { WherePart wherePart = null; if (complexFieldFilter != null) { ICollection<KeyValuePair<string, object>> parameters = new Dictionary<string, object>(); if (complexFieldFilter.BuildCriteria(out string where, parameters)) { wherePart = new WherePart(where, parameters); } } return wherePart; } #endregion #region TableName public SqlBuilder SetTableName<T>() { this.SetTableName(typeof(T).Name); return this; } public SqlBuilder SetTableName(Type tableType) { this.SetTableName(tableType.GetType().Name); return this; } public SqlBuilder SetTableName(string tableName) { this._tableName = $"{START_OPE}{tableName}{END_OPE}"; return this; } #endregion #region Select /// <summary> /// 设置Select子句 /// </summary> /// <param name="selectFields"></param> /// <returns></returns> public SqlBuilder SetSelect(params string[] selectFields) { if (selectFields != null && selectFields.Length > 0) { var list = new List<string>(); foreach (var field in selectFields) { list.Add($"{START_OPE}{field}{END_OPE}"); } this._selectSql = string.Join(",", list); } return this; } /// <summary> /// 设置Select子句（不推荐，性能低） /// </summary> /// <typeparam name="T"></typeparam> /// <param name="propertyExpression"></param> /// <returns></returns> public SqlBuilder SetSelect<T>(params Expression<Func<T, object>>[] propertyExpression) { string[] includePropertyNames = null; if (propertyExpression?.Length > 0) { includePropertyNames = this.GetPropertyNames<T>(propertyExpression); } if (includePropertyNames?.Length > 0) { this.SetSelect(includePropertyNames); } return this; } #endregion #region Where /// <summary> /// 设置条件 /// </summary> /// <param name="whereField"></param> /// <returns></returns> public SqlBuilder SetWhere(FieldFilter whereField) { if (whereField != null) { this.SetWherePart(SqlBuilder.BuildWhere(whereField)); } return this; } /// <summary> /// 设置条件（AND） /// </summary> /// <param name="fieldFilters"></param> /// <returns></returns> public SqlBuilder SetAndWhere(params FieldFilter[] fieldFilters) { if (fieldFilters?.Length > 0) { this.SetWherePart(SqlBuilder.BuildAndWhere(fieldFilters)); } return this; } /// <summary> /// 设置条件（AND） /// </summary> /// <param name="pairs"></param> /// <returns></returns> public SqlBuilder SetAndWhere(ICollection<KeyValuePair<string, object>> pairs) { if (pairs?.Count > 0) { this.SetWherePart(SqlBuilder.BuildAndWhere(pairs)); } return this; } /// <summary> /// 设置条件（OR） /// </summary> /// <param name="FieldFilters"></param> /// <returns></returns> public SqlBuilder SetOrWhere(params FieldFilter[] fieldFilters) { if (fieldFilters?.Length > 0) { this.SetWherePart(SqlBuilder.BuildOrWhere(fieldFilters)); } return this; } /// <summary> /// 设置条件（OR） /// </summary> /// <param name="pairs"></param> /// <returns></returns> public SqlBuilder SetOrWhere(ICollection<KeyValuePair<string, object>> pairs) { if (pairs?.Count > 0) { this.SetWherePart(SqlBuilder.BuildOrWhere(pairs)); } return this; } public SqlBuilder SetWherePart(WherePart wherePart) { if (wherePart != null) { wherePart.Sql = !string.IsNullOrWhiteSpace(wherePart.Sql) ? " WHERE " + wherePart.Sql : string.Empty; this._wherePart = wherePart; } return this; } #endregion; #region Top public SqlBuilder SetTop(int top) { if (top > 0) { string topSql = top.ToString(); this._topSql = SqlBuilder.SQL_DATA_TYPE == ESqlDataType.MySql ? $"LIMIT {topSql}" : $"TOP {topSql}"; } return this; } #endregion #region OrderBy /// <summary> /// /// </summary> /// <param name="orderBys"></param> /// <returns></returns> public SqlBuilder SetOrderBy(Dictionary<string, int> orderByDict) { StringBuilder orderSql = new StringBuilder(); if (orderByDict?.Count > 0) { orderSql.Append(" ORDER BY "); string temp = "ASC"; foreach (var orderField in orderByDict.Keys) { temp = orderByDict[orderField] >= 0 ? "ASC" : "DESC"; orderSql.Append($"{orderField} {temp},"); } this._orderBySql = orderSql.ToString().Trim(','); } return this; } #endregion #region Private private string[] GetPropertyNames<T>(params Expression<Func<T, object>>[] exps) { string[] props = new string[exps.Length]; for (int i = 0; i < exps.Length; i++) { props[i] = this.GetPropertyName(exps[i]); } return props; } private string GetPropertyName<T>(Expression<Func<T, object>> expr) { return EXPRESSION_CACHE.GetOrAdd(expr.GetType(), t => { string rtn = null; if (expr.Body is UnaryExpression) { rtn = ((MemberExpression)((UnaryExpression)expr.Body).Operand).Member.Name; } else if (expr.Body is MemberExpression) { rtn = ((MemberExpression)expr.Body).Member.Name; } else if (expr.Body is ParameterExpression) { rtn = ((ParameterExpression)expr.Body).Type.Name; } return rtn; }); } private static FieldFilter[] BuildFildFilters(ICollection<KeyValuePair<string, object>> pairs) { FieldFilter[] fieldFilters = new FieldFilter[pairs.Count]; int index = 0; string key = string.Empty; object value = null; foreach (var pair in pairs) { key = pair.Key; value = pair.Value; if (value is System.Int32) { int intValue = (Int32)Convert.ChangeType(value, typeof(System.Int32)); fieldFilters[index++] = new EqualFieldFilter<int>(key, intValue); } else if (value is System.Int64) { long longValue = (Int64)Convert.ChangeType(value, typeof(System.Int64)); fieldFilters[index++] = new EqualFieldFilter<System.Int64>(key, longValue); } else// if (value is System.String|| value is System.DateTime) { string strValue = (string)Convert.ChangeType(value, typeof(System.String)); fieldFilters[index++] = new EqualFieldFilter<string>(key, strValue); } } return fieldFilters; } #endregion } public class WherePart { /// <summary> /// 含有参数变量的SQL语句 /// </summary> public string Sql { get; set; } /// <summary> /// SQL语句中的参数变量 /// </summary> public ICollection<KeyValuePair<string, object>> Parameters { get; set; } public WherePart(string sql, ICollection<KeyValuePair<string, object>> parameters) { this.Parameters = parameters; this.Sql = sql; } } public enum ESqlDataType { MySql = 1, SqlServer = 2 }
筛选字段类（FieldFilter）：
/// <summary> /// 筛选抽象基类 /// </summary> [Serializable] public abstract class FieldFilter { private string _fieldName = null; /// <summary> /// 字段名称 /// </summary> public string FieldName { get { return this._fieldName;// $"{SqlBuilder.START_OPE}{this._fieldName}{SqlBuilder.END_OPE}"; } set { this._fieldName = value; } } /// <summary> /// 字段排序先后顺序 /// </summary> internal int FieldOrderByPriority { get; set; } internal abstract bool isEmpty { get; } public bool IsEmpty() { return this.isEmpty; } public abstract bool BuildCriteria(out string where,ICollection<KeyValuePair<string,object>> parameters); } #region - 筛选器字段类 - public class EqualFieldFilter<T> : FieldFilter //where T : struct { public EqualFieldFilter() { } public EqualFieldFilter(string fieldName, T value) { base.FieldName = fieldName; this.Value = value; } //public EqualFieldFilter(string fieldName, T? value) //{ // base.FieldName = fieldName; // this.Value = value; //} public T Value { get; set; } internal override bool isEmpty { get { return false; } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } where = new SimpleExpression(base.FieldName, this.Value, " = ").ToString(parameters); //parameters = new Dictionary<string, object> { { $"@{base.FieldName}",this.Value} }; return true; } } /// <summary> /// 比较筛选条件 /// </summary> /// <typeparam name="T"></typeparam> [Serializable] public class CompareFieldFilter<T> : FieldFilter where T : struct { public CompareFieldFilter() { //this.Operator = CompareOperator.Equal; } public CompareFieldFilter(string fieldName, T value) : this(fieldName, value, "=") { } public CompareFieldFilter(string fieldName, T value, string @operator) { base.FieldName = fieldName; this.Value = value; this.Operator = @operator; } public CompareFieldFilter(string fieldName, T? value) : this(fieldName, value, "=") { } public CompareFieldFilter(string fieldName, T? value, string @operator) { base.FieldName = fieldName; this.Value = value; this.Operator = @operator; } public T? Value { get; set; } /// <summary> /// 获取或者设置 比较类型<see cref="CompareOperator"/> /// 默认值：Equal /// </summary> public string Operator { get; set; } internal override bool isEmpty { get { return !this.Value.HasValue; } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } where = new SimpleExpression(base.FieldName, this.Value, this.Operator).ToString(parameters); return true; } public static explicit operator T(CompareFieldFilter<T> value) { return value.Value.Value; } public static explicit operator T? (CompareFieldFilter<T> value) { return value.Value; } } /// <summary> /// 范围筛选条件 /// </summary> /// <typeparam name="T"></typeparam> [Serializable] public class RangeFieldFilter<T> : FieldFilter where T : struct { public RangeFieldFilter() { } public RangeFieldFilter(string fieldName, T startValue, T endValue) { base.FieldName = fieldName; this.StartValue = startValue; this.EndValue = endValue; } public RangeFieldFilter(string fieldName, T? startValue, T? endValue) { base.FieldName = fieldName; this.StartValue = startValue; this.EndValue = endValue; } public T? StartValue { get; set; } public T? EndValue { get; set; } internal override bool isEmpty { get { return this.StartValue == null && this.EndValue == null; } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } if (this.StartValue != null && this.EndValue != null) { where = new BetweenExpression(base.FieldName, this.StartValue, this.EndValue).ToString(parameters); } return true; } public static explicit operator T[] (RangeFieldFilter<T> value) { return new T[2] { value.StartValue.Value, value.EndValue.Value }; } public static explicit operator T?[] (RangeFieldFilter<T> value) { return new T?[2] { value.StartValue, value.EndValue }; } } /// <summary> /// 多值模式 /// </summary> [Serializable] public enum AnyMode : int { /// <summary> /// 包含这些值 /// </summary> Contain = 0, /// <summary> /// 排除这些值 /// </summary> Exclude = 1 } /// <summary> /// 多值筛选条件 /// </summary> /// <typeparam name="T"></typeparam> [Serializable] public class AnyFieldFilter<T> : FieldFilter { public AnyFieldFilter() { } /// <summary> /// 构造 /// </summary> /// <param name="value">集合值</param> public AnyFieldFilter(string fieldName, IEnumerable<T> value) : this(fieldName, value, AnyMode.Contain) { } /// <summary> /// 构造 /// </summary> /// <param name="value">集合值</param> /// <param name="Mode">多值模式</param> public AnyFieldFilter(string fieldName, IEnumerable<T> value, AnyMode Mode) { base.FieldName = fieldName; this.Value = value; this.Mode = Mode; } public IEnumerable<T> Value { get; set; } public AnyMode Mode { get; set; } internal override bool isEmpty { get { return this.Value == null || !this.Value.Any(); } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } if (this.Value.Count() == 1) { where = new SimpleExpression(base.FieldName, this.Value.First(), " = ").ToString(parameters); } else { switch (this.Mode) { case AnyMode.Contain: where = string.Format("{0} IN ({1})", base.FieldName, string.Join(",", this.Value)); break; case AnyMode.Exclude: where = string.Format("{0} NOT IN ({1})", base.FieldName, string.Join(",", this.Value)); break; } } return true; } } /// <summary> /// 模糊筛选模式 /// </summary> [Serializable] public enum LikeMode : int { /// <summary> /// 任何位置,相当于 like '%value%' /// </summary> AnyWhere = 0, /// <summary> /// 开始处,相当于 like 'value%' /// </summary> Start = 1, /// <summary> /// 结尾处,相当于 like '%value' /// </summary> End = 2 } /// <summary> /// 模糊筛选条件 /// </summary> [Serializable] public class LikeFieldFilter : FieldFilter { public LikeFieldFilter(string fieldName, string value) : this(fieldName, value, LikeMode.AnyWhere) { } public LikeFieldFilter(string fieldName, string value, LikeMode likeMode) { base.FieldName = fieldName; this.Value = value; this.Mode = likeMode; } public string Value { get; set; } /// <summary> /// 匹配模式，默认 AnyWhere /// </summary> public LikeMode Mode { get; set; } internal override bool isEmpty { get { return string.IsNullOrWhiteSpace(this.Value); } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } switch (this.Mode) { case LikeMode.AnyWhere: where = new SimpleExpression(base.FieldName, $"%{this.Value}%", " LIKE ").ToString(parameters); break; case LikeMode.End: where = new SimpleExpression(base.FieldName, $"%{this.Value}", " LIKE ").ToString(parameters); break; case LikeMode.Start: where = new SimpleExpression(base.FieldName, $"{this.Value}%", " LIKE ").ToString(parameters); break; } return true; } } /// <summary> /// 表达式筛选方式 /// </summary> /// <typeparam name="T"></typeparam> public class WhereFieldFilter<T> : FieldFilter where T : class { internal string Value { get; set; } public WhereFieldFilter(string value) { this.Value = value; } internal override bool isEmpty { get { return string.IsNullOrWhiteSpace(this.Value); } } public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters) { where = string.Empty; if (this.isEmpty) { return false; } where = this.Value; return true; } } #endregion #region- 组合筛选器字段类 - public class CombineFieldFilterBase : FieldFilter { protected virtual string Operator { get; } protected FieldFilter[] _fieldFilterList = null; public CombineFieldFilterBase(params FieldFilter[] fieldFilterList) { this._fieldFilterList = fieldFilterList; } internal override bool isEmpty => false; public override bool BuildCriteria(out string where, ICollection<KeyValuePair<string, object>> parameters)// { where = string.Empty; List<string> whereList = new List<string>(); foreach (var fieldFilter in this._fieldFilterList) { if (fieldFilter.BuildCriteria(out string fieldWhere, parameters)) { whereList.Add(fieldWhere); } } if (whereList.Count <= 0) { return false; } where = "(" + string.Join(Operator, whereList) + ")"; return true; } } public class AndFieldFilter : CombineFieldFilterBase { protected override string Operator { get { return " AND "; } } public AndFieldFilter(params FieldFilter[] fieldFilterList) : base(fieldFilterList) { } } public class OrFieldFilter : CombineFieldFilterBase { protected override string Operator { get { return " OR "; } } public OrFieldFilter(params FieldFilter[] fieldFilterList) : base(fieldFilterList) { } } #endregion