Question

am trying convert string to float,when i am passing single char it is giving exceptions.

FMandateSize := StrToFloat(EditMandateSize.Text);

any idea how to convert single char to float?

Answer 1

What floating point value would you expect from a space character? Probably 0.0.

You could use StrToFloatDef to assign your own default value for invalid strings:

FMandateSize := StrToFloatDef(EditMandateSize.Text, 0.0);

Or you could use TryStrToFloat which gives you a boolean result instead of throwing an exception when there’s an invalid string.

Result := TryStrToFloat(EditMandateSize.Text, FMandateSize);