Franz Gleichmann questions

Franz Gleichmann answers

• Why does casting a string as an integer not work?
• C# 6.0 null-conditional operator in if statements
• Sum in array and "undefined index"
• php validation issue End of line character is invalid; expected "\n" but found "\r\n" [duplicate]
• Why the metod app.UseSwaggerUI(...) is not found?
• Remove excess commas from string PHP
• Reduce memory usage for big database calls php