protected override void BuildConverterFunction(Expression from, Type fromType, Type toType)
{
if (toType == Types.Boolean && !hasEnterBoolConvert)
{
//把有符号数转换为无符号数，然后进行转换
if (fromType == Types.SByte ||
fromType == Types.Int16 ||
fromType == Types.Int32 ||
fromType == Types.Int64)
{
hasEnterBoolConvert = true;
from = Expression.Call(typeof(Math).GetMethod("Abs", new Type[] { fromType }), from);
ConvertTo(from, toType);
hasEnterBoolConvert = false;
return;
}
if (fromType == Types.String)
{
hasEnterBoolConvert = true;
from = Expression.Call(typeof(Math).GetMethod("Abs", new Type[] { Types.Int32 })
, Expression.Call(MethodRepository.GetConvertMethod(Types.String, Types.Int32), from));
ConvertTo(from, toType);
hasEnterBoolConvert = false;
return;
}
}
if (toType == Types.DateTime)
{
sb.Append("CONVERT(DATETIME,");
Visit(from);
sb.Append(",20)");
return;
}
if (toType == Types.String)
{
if (fromType == Types.DateTime)
{
//参考：http://www.cnblogs.com/liushanshan/archive/2011/06/30/2094387.html
sb.Append("CONVERT(NVARCHAR(200),");
Visit(from);
sb.Append(",20)");
return;
}
if (fromType == Types.Guid)
{
sb.Append("CAST(");
Visit(from);
sb.Append(" AS NVARCHAR(72))");
return;
}
}
base.BuildConverterFunction(from, fromType, toType);
}
protected override Expression VisitUnary(UnaryExpression u)
{
u = base.VisitUnary(u) as UnaryExpression;
switch (u.NodeType)
{
case ExpressionType.TypeAs:
case ExpressionType.Convert:
case ExpressionType.ConvertChecked:
return(Expression.Call(MethodRepository.GetConvertMethod(u.Operand.Type, u.Type), u.Operand));
}
return(u);
}
protected override void BuildConverterFunction(Expression from, Type fromType, Type toType)
{
if (fromType == Types.Boolean && !hasEnterBoolConvert)
{
//Access 的bool值的True=-1， False=0,所以需要首先把bool转化为整形然后取绝对值，这样bool的True才能转化为1
hasEnterBoolConvert = true;
from = Expression.Call(typeof(Math).GetMethod("Abs", new Type[] { Types.Int32 }), Expression.Call(MethodRepository.GetConvertMethod(Types.Boolean, Types.Int32), from));
ConvertTo(from, toType);
hasEnterBoolConvert = false;
return;
}
if (toType == Types.String)
{
//if (fromType == Types.Guid)
//{
// Visit(from);
// return;
//}
if (fromType == Types.DateTime)
{
sb.Append("FORMAT(");
Visit(from);
sb.Append(",'yyyy-MM-dd HH:mm:ss')");
return;
}
}
if (fromType == Types.String)
{
if (toType == Types.Guid)
{
from = Expression.Call(MethodRepository.ToLower, from);
Visit(from);
return;
}
}
DBType code;
if (!SqlType.TypeMap.TryGetValue(toType.TypeHandle.Value.GetHashCode(), out code))
{
throw new InvalidCastException(string.Format("Cann't convert from '{0}' to db type.", fromType.FullName));
}
var fnView = CastFunctions[code];
fnView.Render(this, from);
}
protected override Expression VisitMethodCall(MethodCallExpression m)
{
m = base.VisitMethodCall(m) as MethodCallExpression;
var lambda = MethodMapping.ConvertMember(m.Method);
if (lambda != null)
{
var ef = lambda.Body.Unwrap();
var parms = new Dictionary <string, ParameterMapping>(lambda.Parameters.Count);
var pn = m.Method.IsStatic ? 0 : -1;
foreach (var p in lambda.Parameters)
{
parms.Add(p.Name, new ParameterMapping(pn++, p.Type));
}
var pie = ef.Convert(wpi =>
{
if (wpi.NodeType == ExpressionType.Parameter)
{
ParameterMapping n;
if (parms.TryGetValue(((ParameterExpression)wpi).Name, out n))
{
var tmp = n.Index < 0 ? m.Object : m.Arguments[n.Index];
if (tmp.Type != n.Type)
{
return(Expression.Convert(tmp, n.Type));
}
return(tmp);
}
}
return(wpi);
});
if (m.Method.ReturnType != pie.Type)
{
pie = Expression.Convert(pie, m.Method.ReturnType);
}
return(Visit(pie));
}
var methodName = m.Method.Name;
var declaringType = m.Method.DeclaringType;
if (declaringType == typeof(System.Convert))
{
Expression operand = null;
Type toType = null;
if (m.Method.Name.StartsWith("To"))
{
toType = ClassLoader.Load("System." + m.Method.Name.Replace("To", ""));
operand = m.Arguments[0];
}
if (operand != null && toType != null && toType != Types.Object)
{
return(Expression.Call(MethodRepository.GetConvertMethod(operand.Type, toType), operand));
}
}
if (typeof(TypeConverter).IsAssignableFrom(declaringType))
{
Expression operand = null;
Type toType = null;
if (methodName.StartsWith("ConvertFrom"))
{
var c = m.Object as ConstantExpression;
Type converterType = null;
if (c != null)
{
converterType = (m.Object as ConstantExpression).Value.GetType();
}
else
{
var ma = m.Object as MemberExpression;
if (ma != null)
{
c = ma.Expression as ConstantExpression;
if (c == null)
{
throw new NotSupportedException(string.Format("The method '{0}' is not supported", m.Method.Name));
}
converterType = ma.Member.GetGetter()(c.Value).GetType();
}
}
toType = ClassLoader.Load("System." + converterType.Name.Replace("Converter", ""));
if (toType == null)
{
throw new NotSupportedException(string.Format("The method '{0}' is not supported", m.Method.Name));
}
if (methodName == "ConvertFrom" && m.Arguments.Count == 1)
{
operand = m.Arguments[0];
}
else if (methodName == "ConvertFromString" && m.Arguments.Count == 1)
{
operand = m.Arguments[0];
}
else if (methodName == "ConvertFromInvariantString" && m.Arguments.Count == 1)
{
operand = m.Arguments[0];
}
}
else if (methodName == "ConvertTo" && m.Arguments.Count == 2)
{
operand = m.Arguments[0];
toType = (m.Arguments[1] as ConstantExpression).Value as Type;
}
else if (methodName == "ConvertToInvariantString" && m.Arguments.Count == 1)
{
operand = m.Arguments[0];
toType = Types.String;
}
else if (methodName == "ConvertToString" && m.Arguments.Count == 1)
{
operand = m.Arguments[0];
toType = Types.String;
}
if (operand != null && toType != null && toType != Types.Object)
{
return(Expression.Call(MethodRepository.GetConvertMethod(operand.Type, toType), operand));
}
throw new NotSupportedException(string.Format("The method '{0}' is not supported", methodName));
}
if (methodName == "Parse" &&
m.Method.IsStatic &&
(declaringType.IsValueType || declaringType.IsNullable()) &&
m.Arguments.Count == 1 &&
m.Method.ReturnType == m.Type)
{
Expression operand = m.Arguments[0];
Type toType = declaringType.IsNullable() ? Nullable.GetUnderlyingType(declaringType) : declaringType;
return(Expression.Call(MethodRepository.GetConvertMethod(operand.Type, toType), operand));
}
if (declaringType == Types.String)
{
if (methodName == "Concat")
{
return(BindConcat(m.Arguments.ToArray()));
}
if (methodName == "Join")
{
return(BindJoin(m));
}
}
if (methodName == "ContainsValue" && IsSameOrParent(typeof(IDictionary <,>), declaringType))
{
var args = GetGenericArguments(declaringType, typeof(IDictionary <,>));
var minf = EnumerableMethods
.First(s => s.Name == "Contains" && s.GetParameters().Length == 2)
.MakeGenericMethod(args[1]);
return(Expression.Call(
minf,
Expression.PropertyOrField(m.Object, "Values"),
m.Arguments[0]));
}
if (methodName == "ContainsKey" && IsSameOrParent(typeof(IDictionary <,>), declaringType))
{
var args = GetGenericArguments(declaringType, typeof(IDictionary <,>));
var minf = EnumerableMethods
.First(s => s.Name == "Contains" && s.GetParameters().Length == 2)
.MakeGenericMethod(args[1]);
return(Expression.Call(
minf,
Expression.PropertyOrField(m.Object, "Keys"),
m.Arguments[0]));
}
if (declaringType.FullName == DLinq.StrSqlMethhodsType && declaringType.Assembly.GetName().Name == DLinq.StrAssemblyName)
{
DLinq.Init(declaringType.Assembly);
return(Visit(m));
}
//if (methodName == "Like" && declaringType == typeof(SqlFunctions) && m.Arguments.Count == 5)
//{
// return BindLike(
// m.Arguments[0]
// , m.Arguments[1]
// , (bool)(m.Arguments[2] as ConstantExpression).Value
// , (bool)(m.Arguments[3] as ConstantExpression).Value
// , (bool)(m.Arguments[4] as ConstantExpression).Value);
//}
if (typeof(Queryable).IsAssignableFrom(declaringType) || typeof(Enumerable).IsAssignableFrom(declaringType))
{
var elementType = NLite.Data.Linq.Internal.ReflectionHelper.GetElementType(m.Arguments[0].Type);
switch (methodName)
{
case "Contains":
EntityMapping mapping;
if (DbContext.dbConfiguration.mappings.TryGetValue(elementType.TypeHandle.Value, out mapping))
{
// Expression left =
}
break;
//case "Aggregate":
// {
// var type = NLite.Reflection.TypeHelper.GetElementType(m.Arguments[0].Type);
// if (type.IsNullable())
// type = Nullable.GetUnderlyingType(type);
// if (type.IsClass && type != Types.String)
// throw new NotSupportedException("Not support 'Aggregate' function for complex type.");
// break;
// }
//case "ElementAt":
// var index = m.Arguments[1];
// var elementType = NLite.Reflection.TypeHelper.GetElementType(m.Arguments[0].Type);
// var c = index as ConstantExpression;
// if (c != null)
// {
// if((int)c.Value == 0)
// return Expression.Call(typeof(Enumerable), "Take", new Type[] { elementType }, m.Arguments[0], Expression.Constant(1, Types.Int32));
// index = Expression.Constant((int)c.Value + 1, Types.Int32);
// }
// else
// index = Expression.Add(index, Expression.Constant(1, Types.Int32));
// var s = Expression.Call(typeof(Enumerable), "Skip", new Type[] { elementType },m.Arguments[0], index);
// return Expression.Call(typeof(Enumerable), "Take", new Type[] { elementType },s, Expression.Constant(1,Types.Int32));
}
}
if (IsSameOrParent(typeof(IEnumerable <>), declaringType) &&
!declaringType.IsArray &&
m.Object != null &&
m.Object.NodeType == ExpressionType.Constant &&
!typeof(IQueryable).IsAssignableFrom(declaringType))
{
switch (methodName)
{
case "Contains":
var elementType = NLite.Data.Linq.Internal.ReflectionHelper.GetElementType(declaringType);
if (!DbContext.dbConfiguration.HasClass(elementType) && elementType != Types.Char)
{
var lst = (m.Object as ConstantExpression).Value as IEnumerable;
if (lst != null)
{
var items = lst.Cast <object>().ToArray();
var arry = Array.CreateInstance(elementType, items.Length);
for (int i = 0; i < items.Length; i++)
{
arry.SetValue(items[i], i);
}
Expression array = Expression.Constant(arry);
var containsMethod = EnumerableMethods
.First(s => s.Name == "Contains" && s.GetParameters().Length == 2)
.MakeGenericMethod(elementType);
m = Expression.Call(containsMethod, array, m.Arguments[0]);
}
}
break;
}
}
return(m);
}