public SelectParser(LambdaExpression _LambdaExpression, StringBuilder Code, Dictionary <string, string> Alias)
{
if (_LambdaExpression.Body is ConstantExpression)//如果是字符串
{
var body = (_LambdaExpression.Body as ConstantExpression);
foreach (var item in _LambdaExpression.Parameters)
{
Alias.Add(item.Name, ReflexHelper.GetTableAttribute(item.Type).TableName);
}
var values = body.Value.ToStr();
Code.Append((string.IsNullOrEmpty(values) ? "*" : values));
}
else if (_LambdaExpression.Body.Type == typeof(string))//如果是字符串
{
var value = Parser.Eval(_LambdaExpression.Body).ToStr();
Code.Append((string.IsNullOrEmpty(value) ? "*" : value));
}
else if (_LambdaExpression.Body is NewExpression)//如果是匿名对象
{
var body = (_LambdaExpression.Body as NewExpression);
var values = body.Arguments;
var member = body.Members;
var column = new List <string>();
foreach (var item in _LambdaExpression.Parameters)
{
Alias.Add(item.Name, ReflexHelper.GetTableAttribute(item.Type).TableName);
}
var list_member = member.ToList();
foreach (var item in values)
{
if (item is MemberExpression)
{
var it = item as MemberExpression;
//检查是否有别名
var DisplayName = list_member[values.IndexOf(item)].Name;
if (DisplayName == it.Member.Name)
{
column.Add((it.Expression as ParameterExpression).Name + "." + it.Member.Name);
}
else
{
column.Add((it.Expression as ParameterExpression).Name + "." + it.Member.Name + " AS " + DisplayName);
}
}
else if (item is ConstantExpression)
{
var it = item as ConstantExpression;
var val = it.Value;
//检查是否有别名 ''
var DisplayName = list_member[values.IndexOf(item)].Name;
if (!string.IsNullOrEmpty(DisplayName))
{
//判断别名是否 有 SqlString 关键字
if (DisplayName.StartsWith("SqlString"))
{
column.Add(val.ToStr());
}
else
{
column.Add(" '" + val + "' " + " AS " + DisplayName);
}
}
}
else if (item.Type == typeof(string))
{
//检查是否有别名 ''
var value = Parser.Eval(item).ToStr();
var DisplayName = list_member[values.IndexOf(item)].Name;
if (!string.IsNullOrEmpty(DisplayName) && DisplayName.StartsWith("SqlString"))
{
column.Add(value);
}
}
}
Code.Append(string.Join(",", column));
}
else
{
Code.Append("*");
}
}
