Format item index too large

• Apr 29, 2019

CodeRush Classic shows the Format item index too large code issue if a format item index is greater then or equal to the number of arguments passed to the String.Format.

Fix

Correct the format item index or add arguments to the String.Format call.

Purpose

Highlights format items with indices greater then or equal to the number of arguments passed to the String.Format; this action will cause the FormatException exception.

Example

C#

string fileName = "Settings.xml";
string settingsPath = string.Format("C:\\MyApp\\{0}\\{1}", fileName);

Fix:

C#

string fileName = "Settings.xml";
string subfolder = "Settings;"
string settingsPath = string.Format("C:\\MyApp\\{0}\\{1}", subfolder, fileName);