Passing parameters

1. Call by Value:
• When formal arguments are modified, if the modification is not reflected on the actual arguments then the concept is called "Call by value".
2. Call By Reference (ref):
• When formal arguments are modified, if the modification is reflected on the actual arguments then the concept is called "Call By Reference".
• The ref modifier causes the arguments to be passed by reference.
• The ref modifier has to be used along with formal & actual arguments i.e., the ref keyword has to be used in the method definition and the code that calls it.
• The ref variable must be initializing before passing.
3. Call By Out (out):
• The Out parameter is used in cases where you need to return a value from a method, but not pass a value to the method.
• Use Out parameter to return more than one value from the method.
• The Out parameter will not have any initial values but must be assigned a value before the method terminates.