Validate on Multiline textbox 100 characters per line on copy paste

Hi,

Im having a multiline textbox in windows form.User can enter the words or they can copy and paste the words,paragraphs.

Restriction is user can enter only 100 characters per line.I had wrote a code to validate in TextChanged event if the user typing the words.But I dont know in which event I need to write validation if the user copy and paste.

Text changed event fires on copy paste also.BUt the validation which wrote in text changed event wont work for copy paste.

Because it is line specific.

Please help me to validate for copy paste and also user types manually.