public string GetSql(Expression expr)
{
Result.Clear();
if (expr.Type == typeof(bool) && expr.NodeType == ExpressionType.MemberAccess)
{
expr = ExpressionsHelper.GetBinaryExpression(expr);
}
Visit(expr);
return(Result.ToString());
}
public virtual IResult Resolve <TEntity>(Expression expression) where TEntity : class
{
EntityMetadata = EntityMetadata.Parse <TEntity>();
Result = new DbResolveResult();
if (expression.Type == typeof(bool) && expression.NodeType == ExpressionType.MemberAccess)
{
expression = ExpressionsHelper.GetBinaryExpression(expression);
}
Visit(expression);
return(Result);
}
protected override Expression VisitBinary(BinaryExpression b)
{
var left = b.Left;
var right = b.Right;
var boolOperators = new[] { ExpressionType.AndAlso, ExpressionType.OrElse };
if (boolOperators.Contains(b.NodeType))
{
left = left.NodeType == ExpressionType.MemberAccess ? ExpressionsHelper.GetBinaryExpression(left) : left;
right = right.NodeType == ExpressionType.MemberAccess ? ExpressionsHelper.GetBinaryExpression(right) : right;
}
var dialect = Configuration.Dialect;
Result.Append(dialect.Symbol(SqlSymbols.StartGroup));
this.Visit(left);
switch (b.NodeType)
{
case ExpressionType.And:
Result.Append($" {dialect.Keyword(SqlKeyword.And)} ");
break;
case ExpressionType.AndAlso:
Result.Append($" {dialect.Keyword(SqlKeyword.And)} ");
break;
case ExpressionType.Or:
Result.Append($" {dialect.Keyword(SqlKeyword.Or)} ");
break;
case ExpressionType.OrElse:
Result.Append($" {dialect.Keyword(SqlKeyword.Or)} ");
break;
case ExpressionType.Equal:
if (IsNullConstant(b.Right))
{
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.Is)} ");
}
else
{
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.Equal)} ");
}
break;
case ExpressionType.NotEqual:
if (IsNullConstant(b.Right))
{
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.IsNot)} ");
}
else
{
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.NotEqual)} ");
}
break;
case ExpressionType.LessThan:
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.LessThan)} ");
break;
case ExpressionType.LessThanOrEqual:
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.LessThanOrEqual)} ");
break;
case ExpressionType.GreaterThan:
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.GreaterThan)} ");
break;
case ExpressionType.GreaterThanOrEqual:
Result.Append($" {dialect.ComparisonSymbol(SqlComparison.GreaterThanOrEqual)} ");
break;
case ExpressionType.Add:
Result.Append($" {dialect.ArithMeticOperand(SqlArithmeticOperand.Add)} ");
break;
case ExpressionType.Subtract:
Result.Append($" {dialect.ArithMeticOperand(SqlArithmeticOperand.Subtract)} ");
break;
case ExpressionType.Multiply:
Result.Append($" {dialect.ArithMeticOperand(SqlArithmeticOperand.Multiply)} ");
break;
case ExpressionType.Divide:
Result.Append($" {dialect.ArithMeticOperand(SqlArithmeticOperand.Divide)} ");
break;
default:
throw new NotSupportedException(string.Format("The binary operator '{0}' is not supported", b.NodeType));
}
this.Visit(right);
Result.Append(dialect.Symbol(SqlSymbols.EndGroup));
return(b);
}
protected override Expression VisitBinary(BinaryExpression b)
{
var left = b.Left;
var right = b.Right;
var boolOperators = new[] { ExpressionType.AndAlso, ExpressionType.OrElse };
if (boolOperators.Contains(b.NodeType))
{
left = left.NodeType == ExpressionType.MemberAccess ? ExpressionsHelper.GetBinaryExpression(left) : left;
right = right.NodeType == ExpressionType.MemberAccess ? ExpressionsHelper.GetBinaryExpression(right) : right;
}
var builder = (Result as DbResolveResult).Builder;
builder.Append(Dialect.StartGroup);
this.Visit(left);
switch (b.NodeType)
{
case ExpressionType.And:
builder.Append($" {Dialect.And} ");
break;
case ExpressionType.AndAlso:
builder.Append($" {Dialect.And} ");
break;
case ExpressionType.Or:
builder.Append($" {Dialect.Or} ");
break;
case ExpressionType.OrElse:
builder.Append($" {Dialect.Or} ");
break;
case ExpressionType.Equal:
if (ExpressionsHelper.IsNullConstant(b.Right))
{
builder.Append($" {Dialect.Is} ");
}
else
{
builder.Append($" {Dialect.Equal} ");
}
break;
case ExpressionType.NotEqual:
if (ExpressionsHelper.IsNullConstant(b.Right))
{
builder.Append($" {Dialect.IsNot} ");
}
else
{
builder.Append($" {Dialect.NotEqual} ");
}
break;
case ExpressionType.LessThan:
builder.Append($" {Dialect.LessThan} ");
break;
case ExpressionType.LessThanOrEqual:
builder.Append($" {Dialect.LessThanOrEqual} ");
break;
case ExpressionType.GreaterThan:
builder.Append($" {Dialect.GreaterThan} ");
break;
case ExpressionType.GreaterThanOrEqual:
builder.Append($" {Dialect.GreaterThanOrEqual} ");
break;
default:
throw new NotSupportedException($"The binary operator '{b.NodeType}' is not supported");
}
this.Visit(right);
builder.Append(Dialect.EndGroup);
return(b);
}
