public Func <object, Expression <Func <T, bool> > > GetPredicateBuilder <T>(MemberExpression propertyPath)
{
return(valueToCheck =>
{
ConstantExpression valueToCheckConstant = Expression.Constant(valueToCheck);
MethodCallExpression indexOfCall =
Expression.Call(Expression.Coalesce(propertyPath, Expression.Constant(String.Empty)), _indexOfMethod,
valueToCheckConstant,
Expression.Constant(StringComparison.InvariantCultureIgnoreCase));
var operation = _negate ? ExpressionType.LessThan : ExpressionType.GreaterThanOrEqual;
BinaryExpression comparison = Expression.MakeBinary(operation, indexOfCall,
Expression.Constant(0));
ParameterExpression lambdaParameter = propertyPath.GetParameter <T>();
return Expression.Lambda <Func <T, bool> >(comparison, lambdaParameter);
});
}
public Func <object, Expression <Func <T, bool> > > GetPredicateBuilder <T>(MemberExpression propertyPath)
{
return(expected =>
{
Debug.WriteLine("Building expression for " + _comparisonType);
ConstantExpression expectedHolder = propertyPath.Member is PropertyInfo
? Expression.Constant(expected, propertyPath.Member.As <PropertyInfo>().PropertyType)
: Expression.Constant(expected);
BinaryExpression comparison = Expression.MakeBinary(_comparisonType, propertyPath, expectedHolder);
ParameterExpression lambdaParameter = propertyPath.GetParameter <T>();
return Expression.Lambda <Func <T, bool> >(comparison, lambdaParameter);
});
}
public Func <object, Expression <Func <T, bool> > > GetPredicateBuilder <T>(MemberExpression propertyPath)
{
return(valueToCheck =>
{
ConstantExpression valueToCheckConstant = Expression.Constant(valueToCheck);
BinaryExpression binaryExpression = Expression.Coalesce(propertyPath, Expression.Constant(string.Empty));
ConstantExpression invariantCulture = Expression.Constant(StringComparison.InvariantCultureIgnoreCase);
Expression expression = Expression.Call(binaryExpression, _method, valueToCheckConstant, invariantCulture);
if (_negate)
{
expression = Expression.Not(expression);
}
ParameterExpression lambdaParameter = propertyPath.GetParameter <T>();
return Expression.Lambda <Func <T, bool> >(expression, lambdaParameter);
});
}
