Health monitoring for your web application in aspx?

Hello,

I want to create a custom health monitoring for my web application in aspx, how do I do it?

Here is my task, create a health monitoring in aspx page to check your web application, if your web application fails for some reasons like "the page cannot be found" , server was down or disconnect to the database, write out to the web page " Test failed" and the reason why it failed, otherwise, write out to the page "All tests passed".  Can anyone help me with this? if possible, a sample code please.  Thanks in advance.
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