TOPIC:

Guys, Wolfgang,
just found "the" thing about interpolated strings, and thought maybe i'm not the only one a bit slow

VAR i:= 4 AS INT
VAR c AS STRING
c:= i"Bla {i} blabla"

i.e.: the syntax allows to insert ANY type into a string, handling silently the conversions! That's really cool.

Even something like
c:= i"Bla {oMainWindow} blabla"
works, inserting the classname.

So you might consider adding/adapting the docs, as up2now the samples insert only strings, which is relatively pointless
Karl

Hi Karl,
Currently I am on holiday, will add better samples after my return.
Wolfgang

Ey, saw your "status" in whatsapp - cool location....
Enjoy your free days, i'm almost at the end of mine <sigh>

Karl

Hi Karl,

I'm eagerly waiting for the next C# feature to become true.

local dw as dword

dw := 12_123_789

instead of the boring

dw := 12123789



regards
Karl-Heinz

I like that a lot, too!

Could it be that you didn't get the drift of my post?
All samples i saw for i"..." used strings as insertion, and that is really old, as i can do the same with simple +...+, so i never understood the usecase
But for any other type it comes handy...

K.

? 12.22 + " " + today() + " " + setcentury() + " " + 12123789

Maybe even that will work someday

? 12.22 + " " + today() + " " + setcentury() + " " + 12_123_789

That all works (but only) for "?"...

Mmm, that (underscore delimiters inside numeric literals) should not be too difficult to implement I think.
I'll see what I can do.
Robert

I use this a lot. I have an old C# application built around datasets and i use this when building sql strings.

plInfo.SqlUpdate =
$@"UPDATE {Const.TBL_PRICE_LIST_STRUCT}
SET
{Const.COL_COLUMN_NUM} = {dataReader.SqlValueString(Const.COL_COLUMN_NUM)}
,{Const.COL_START_POSITION} = {dataReader.SqlValueString(Const.COL_START_POSITION)}
,{Const.COL_END_POSITION} = {dataReader.SqlValueString(Const.COL_END_POSITION)}
,{Const.COL_IS_ACTIVE} = {dataReader.SqlValueString(Const.COL_IS_ACTIVE)}
,{Const.COL_IMPORT_FORMAT} = {dataReader.SqlValueString(Const.COL_IMPORT_FORMAT)}
,{Const.COL_EDIT_UID} = {dataReader.SqlValueString(Const.COL_EDIT_UID)}
,{Const.COL_EDIT_DATE} = '{YYYYMMDDHHMMSS}'
,{Const.COL_CREATE_UID} = {dataReader.SqlValueString(Const.COL_CREATE_UID)}
,{Const.COL_CREATE_DATE} = {dataReader.SqlValueString(Const.COL_CREATE_DATE)}
,{Const.COL_PRICE_FORMAT_NUM} = {dataReader.SqlValueString(Const.COL_PRICE_FORMAT_NUM)}
WHERE {Const.COL_PLS_NUM} = {dataReader.SqlValueString(Const.COL_PLS_NUM)}";

Now, it didn't look that good in my message, but in the souce code it's formatted so that all equals are on the same tab level. This makes it really readable, and a lot better than adding strings together.

/Mathias

and one more thing...

This is the method for formatting values for sql expressions. When I format the date you can see that it's also possible to select which date format to use. I suppose this is possible in XSharp as well.

public static class DataReaderExtensions
{
public static string SqlValueString(this SqlDataReader reader, string colName)
{
object value = reader[colName];
Type type = value.GetType();

if (type == typeof(DBNull))
return "NULL";

if (ArrayHelper.InList(type,typeof(string),typeof(bool)))
return $"'{value}'";

if (type == typeof(DateTime))
return $"'{value:s}'";

return $"{value}";
}
}

/Mathias

Don't get me wrong, but what exactly has this to do with interpolated strings?

K.

It's examples of interpolated strings.
/Mathias

FFF wrote: Don't get me wrong, but what exactly has this to do with interpolated strings?

K.

Hi Karl,

I was also confused at first, but $ is the symbol c# uses to specify interpolated strings, Matthias's sample code is full of them

Chris

Hi Karl,

since I have been returned from my trip to the US (South Carolina and Georgia), I have changed the topic in the wiki:

docs.xsharp.it/doku.php?id=strings

Please let me know if I should add or change something else.

Wolfgang

Hi Wolfgang,
hope you had a good trip.
Had a look, seems fine. Maybe in:
cString := ei"this is a \"string\". that references {cLocalVar}"
i'd use:
cString := ei"this is a \"string\", which resolves {xWhateverExpression}"

Lazy folks (like me ) might skip the new line you added behind. Also the "LocalVar" term implies, that there's a harder restriction of what may be used.

Karl

Hi Karl,

I have changed the article again, hopefully it is easier to understand now. Interpolated and extended strings are a really useful thing.

Wolfgang

P.S. yes, my holiday was great (and too short as all of them). We have hiked a lot and seen many animals (including alligators) in their habitats.

Hi,

sorry for not explaining more...

Yes, In C# you use $ for interpolated strings and @ for verbatim strings. The two things I wanted to show were;

1. SQL-statement (or text file row creation) strings can get a lot more readable with interpolated strings and verbatim strings in combination. If you compare with using StringBuilder or string concatination with +, there is a really big difference. As you can see I have all field names as constants which is really usefull if you want to find all occurrences of a field.
2. You can also specify the format. In my case I specified the date format in the SqlValueString method. You can also format numbers in a similar way.

/Mathias

Found one more example of date formating that I have used. This one may be a little more useful....

In this case a filename is constructed by combining a language resource string with a formatted date.
string fileName = $"{AutoUpdatePricelistsFormLabels.LostPriceLinks} {DateTime.Now:yyyyMMdd HHmmss}.xlsx";

/Mathias