public static Sql Delete <TModel>(Expression <Func <TModel, bool> > exp) where TModel : class, new()
{
Sql sql = new Sql();
string tableName = typeof(TModel).Name;
StringBuilder text = new StringBuilder();
text.Append($"DELETE {tableName}");
if (exp != null)
{
text.Append("WHERE ");
string whereStr = SqlBuilderExpression.ResolveExpression(exp);
if (string.IsNullOrEmpty(whereStr))
{
throw new ArgumentNullException($"解析{nameof(exp)} 出错");
}
text.Append(whereStr);
sql.Where = whereStr;
sql.TableNames = new List <string>()
{
tableName
};
sql.Commandtext = text.ToString();
}
return(sql);
}
//多表
private static Sql Find(Expression exp)
{
Sql sql = new Sql();
StringBuilder text = new StringBuilder();
text.AppendLine("SELECT ");
if (exp == null)
{
throw new Exception(nameof(exp));
}
List <string> tableNames = new List <string>();
if (exp is LambdaExpression)
{
LambdaExpression lambdaExpression = exp as LambdaExpression;
List <ParameterExpression> parameterExpressions = lambdaExpression.Parameters.ToList();
if (parameterExpressions == null)
{
throw new Exception(nameof(parameterExpressions));
}
var index = 0;
foreach (var parameterExpression in parameterExpressions)
{
if (index == parameterExpressions.Count - 1)
{
text.AppendLine($"{parameterExpression.Type.Name}.* ");
}
else
{
text.AppendLine($"{parameterExpression.Type.Name}.*, ");
}
index++;
sql.ColumnNames.Add($"{parameterExpression.Type.Name}.*, ");
}
text.AppendLine($"FROM [{parameterExpressions.FirstOrDefault().Type.Name }] AS {parameterExpressions.FirstOrDefault().Type.Name }");
sql.TableNames.Add(parameterExpressions.FirstOrDefault().Type.Name);
//条件
string on = SqlBuilderExpression.ResolveExpression(exp, isAppendTalbeName: true);
List <string> onSplits = on.Split(new string[] { "\r\n" }, StringSplitOptions.None)?.ToList();
var talbleNameIndex = 1;
for (int i = 0; i < onSplits.Count; i++)
{
if (onSplits[i].Equals(JoinType.InnerJoin) || onSplits[i].Equals(JoinType.LeftJoin))
{
onSplits[i] = $"{onSplits[i]} {parameterExpressions[talbleNameIndex].Type.Name} On";
sql.TableNames.Add(parameterExpressions[talbleNameIndex].Type.Name);
talbleNameIndex++;
}
}
text.AppendLine(string.Join(" ", onSplits));
sql.Commandtext = text.ToString();
return(sql);
}
else
{
throw new Exception("不是 LambdaExpression表达式,无法解析");
}
}
public static Sql Update <TModel>(TModel model, Expression <Func <TModel, bool> > exp) where TModel : class, new()
{
Sql sql = new Sql();
string tableName = model.GetType().Name;
var ps = model.GetType().GetProperties();
StringBuilder text = new StringBuilder();
text.Append($"UPDATE {tableName} SET ");
foreach (var p in ps)
{
//跳过主健
if (p.PropertyType.Name.Equals("Id", StringComparison.OrdinalIgnoreCase))
{
continue;
}
if (p.PropertyType.IsArray)
{
continue;
}
if (p.PropertyType.IsGenericType)
{
continue;
}
if (p.PropertyType.IsGenericTypeDefinition)
{
var objValue = ReflectionHelper.ChangeValue(p, p.GetValue(model));
var colunmName = p.PropertyType.GetGenericArguments().FirstOrDefault().Name;
sql.ColumnNames.Add(colunmName);
text.Append($"[{colunmName}] = {objValue}");
}
else
{
var objValue = ReflectionHelper.ChangeValue(p, p.GetValue(model));
var colunmName = p.Name;
text.Append($"[{colunmName}] = {objValue}");
}
}
if (exp != null)
{
text.Append("WHERE ");
string whereStr = SqlBuilderExpression.ResolveExpression(exp);
if (string.IsNullOrEmpty(whereStr))
{
throw new ArgumentNullException($"解析{nameof(exp)} 出错");
}
text.Append(whereStr);
sql.Where = whereStr;
sql.TableNames = new List <string>()
{
tableName
};
sql.Commandtext = text.ToString();
}
return(sql);
}
public QueryExpression <TModel> Or(Expression <Func <TModel, bool> > exp)
{
if (StringWhere.ToString().Substring(0, @where.Length) != where)
{
throw new Exception($"调用Add之前先调用 {nameof(True)} 方法 ");
}
StringWhere.AppendLine($" Or {SqlBuilderExpression.ResolveExpression(exp, isAppendTalbeName: true)}");
return(this);
}
public static Sql GetMin <TModel, TColunmType>(Expression <Func <TModel, TColunmType> > exp) where TModel : class, new()
{
Sql sql = new Sql();
string tableName = typeof(TModel).Name;
if (exp == null)
{
throw new ArgumentNullException(nameof(exp));
}
string maxColumnName = SqlBuilderExpression.ResolveExpression(exp);
StringBuilder text = new StringBuilder();
text.AppendLine($"SELECT Min({maxColumnName}) FROM [{tableName}] ");
sql.Commandtext = text.ToString();
return(sql);
}
/// <summary>
/// 一表,视图
/// </summary>
/// <typeparam name="TModel"></typeparam>
/// <param name="exp"></param>
/// <returns></returns>
public static Sql GetList <TModel>(Expression <Func <TModel, bool> > exp) where TModel : class, new()
{
Sql sql = new Sql();
var selectSql = Find <TModel>(1);
StringBuilder text = new StringBuilder();
text.AppendLine(selectSql);
if (exp == null)
{
throw new ArgumentNullException($"{nameof(exp)} ");
}
StringBuilder where = new StringBuilder();
where.AppendLine("WHERE 1= 1");
where.AppendLine(SqlBuilderExpression.ResolveExpression(exp));
if (string.IsNullOrEmpty(where.ToString()))
{
throw new ArgumentNullException($"解析{nameof(exp)} 出错");
}
text.AppendLine(where.ToString());
sql.Commandtext = text.ToString();
sql.Where = where.ToString();
return(sql);
}
