Replace only whole word in javascript [duplicate]

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Match and replace whole words in javascript

I want to replace in JavaScript the word "microsoft" with "stackoverflow".

But I only want it to replace the whole word - so I don't want "microsoft microsftttt" 开发者_Python百科to be turned into "stackoverflow stackoverflowttt".

You can add ' ' to begin of string & end of string, replace ' microsoft ' to ' stackoverflow ' and cut ' ' , added before it