public static Expression BuildAndConvert(Expression expression, DbCommandBuilder builder, IServiceProvider serviceProvider, bool isJson)
{
var visitor = new RoscoeExpressionVisitor(builder, serviceProvider, Expression.Parameter(typeof(JValue)));
var result = visitor.Visit(expression);
serviceProvider.GetRequiredService <IRoscoeExpressionValueFactory>()
.Create(visitor.columns, isJson)
.Build(builder, serviceProvider);
return(result);
}
public static Expression <Func <JToken, T> > BuildAndConvert <T>(Expression <Func <T> > expression, DbCommandBuilder builder, IServiceProvider serviceProvider, bool isJson)
{
var parameter = Expression.Parameter(typeof(JToken));
var visitor = new RoscoeExpressionVisitor(builder, serviceProvider, parameter);
if (visitor.Visit(expression) is Expression <Func <T> > result)
{
serviceProvider.GetRequiredService <IRoscoeExpressionValueFactory>()
.Create(visitor.columns, isJson)
.Build(builder, serviceProvider);
return(Expression.Lambda <Func <JToken, T> >(result.Body, parameter));
}
throw new Exception("Could not convert expression");
}
public void Build(DbCommandBuilder builder, IServiceProvider serviceProvider)
{
if (Expression != null)
{
var environmentOption = serviceProvider.GetRequiredService <EnvironmentOption>();
builder.SqlBuilder.Write("select ");
var aliasOption = serviceProvider.GetRequiredService <AliasOption>();
var oldAliasOption = aliasOption.Clone();
aliasOption.EmitWithAlias = true;
aliasOption.EmitTable = true;
ConvertExpression = RoscoeExpressionVisitor.BuildAndConvert(Expression, builder, serviceProvider, !environmentOption.IsSubQuery);
builder.SqlBuilder.WriteLine();
aliasOption.Restore(oldAliasOption);
}
}