Have a .Text Expression in C# Code

MarkusRMarkusR
in FastReport .NET

Hello,

because we get updated Report we like to have all settings in Report Source Code at one place.

we have a Text Field with a expression like .Text ="[fieldname]"

i made a function to replace this text it looks like [ChangeMe([fieldname])] that works well in report designer UI.

now i need the same within C# but it seems the function is not found at report preview .

having MyTextField.Text = "[ChangeMe([fieldname])]" run into error.

please help :)

Comments

  • calwayNLcalwayNL

    This is an older post, but I think you should be someting like this:

    MyTextField.Text = ChangeMe((string)Report.GetColumValue("fieldname"));

    So I would think "fieldname" will have to become "datasource.fieldname". ChangeMe should then also be a C# function that is called with a string argument and returns another string?

  • MarkusRMarkusR

    thanks, we will test some day.

  • stgstg

    Hello!

    The thing is that [...] this is a FastReport .NET expression; it is compiled by the report script during the `Prepare()` method. Assigning `Text` from C# does not add the function to the script: `ChangeMe` must either be in the script of the loaded .frx file or registered as a static report function.

    Calculate the value in C# and substitute the finished string — then FastReport won’t attempt to compile the expression:

    var column = (string)report.GetColumnValue(‘Items.fieldname’);

    myTextField.Text = ChangeMe(column); // without square brackets

    Alternatively, register it afterwards as shown in our article: https://www.fast-report.com/blogs/custom-libraries-functions-designer

This discussion has been closed.

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