Debug

Debug

A static class in the System.Diagnostics namespace used to emit debugging information and check program logic with assertions. Its methods are primarily intended for debug builds. Domain: C# → .NET → System.Diagnostics → Debugging Output & Assertions

Debug.Write("Loading…");

Writes debugging information without automatically adding a new line.

Debug.WriteLine("Program started");

Writes debugging information followed by a line terminator.

Debug.WriteLine(value);

Writes the value of an object to the debug listeners by using the object's ToString() representation.

Debug.WriteLine("Connected", "Network");

Writes a debugging message together with a category name that can help identify the type or source of the message.

Debug.WriteIf(condition, "Value is invalid");

Writes the specified debugging message only when the Boolean condition is true.

Debug.WriteLineIf(condition, "Value is invalid");

Writes the specified debugging message followed by a new line only when the Boolean condition is true.

Debug.Assert(age >= 0);

Checks that the specified condition is true and reports an assertion failure when the condition is false.

Debug.Assert(age >= 0, "Age cannot be negative");

Checks a condition and reports the supplied message if the assertion fails.

Debug.Assert(value != null, "Value must not be null", "Check the initialization logic.");

Checks a condition and provides additional diagnostic information when the assertion fails.

Debug.Fail("Unexpected code path reached");

Emits an assertion failure indicating that execution reached a location that should not normally be reached.

Debug.Fail("Invalid state", "State should have been initialized earlier.");

Emits an assertion failure with both a primary message and additional diagnostic details.

Debug.Indent();

Increases the indentation level applied to subsequent Debug output.

Debug.Unindent();

Decreases the indentation level applied to subsequent Debug output.

Debug.IndentLevel = 2;

Sets the current indentation level used for Debug output.

int level = Debug.IndentLevel;

Gets the current indentation level used by Debug output.

Debug.IndentSize = 4;

Sets the number of spaces represented by each indentation level.

int size = Debug.IndentSize;

Gets the number of spaces used for each Debug indentation level.

Debug.Flush();

Flushes buffered debugging output to the attached trace listeners.

Debug.Close();

Flushes output and closes the trace listeners associated with Debug.

Assertion

A debugging check that verifies an expected condition in program logic and reports a failure when that condition is false.

Debug vs Console.WriteLine

Debug.WriteLine() is intended for diagnostic/debugging output and is conditionally compiled for DEBUG builds, whereas Console.WriteLine() writes ordinary program output to the console during normal execution.