Variables that are used before assignment can result in null reference exceptions at runtime

Assign an initial value to the tid, taddress, tphone, and tbanknumber variables.

This warning is because there may be cases where DR is not assigned, and DR is null when the try block throws an exception and enters finally.

You can change dim dr as sqldatareader to dim dr as sqldatareader = nothing to eliminate this warning. However, in order to avoid this situation, you can add a judgment:

If dr isnot nothing thenmyconn, mycommand is similar.

In a word, variables must be defined before they are used.

You can set a mandatory type declaration in the options to avoid the above problems.

I haven't used it, but I just checked it on the Internet There is no difference in the grammar of the two versions.,It's that in some places, 03's can be used and 05's can't.,It's recommended to use a version.,Don't change versions all the time.。

You can leave it alone, because the default value is empty, and if you want to avoid warnings, you can define it as: dim msgtext as string=""

Your function is going to return a value.

For example: function myfunc(byval b as boolean) as string

if b = true then

return "Return"

end if

end function

Write the return value according to your own requirements.

It can be string, boolean, int, etc.

ffunction myfunc(byval b as boolean) as string

if b = true then

return "Return"

end if

end function

Write the return value according to your own requirements.

It can be string, boolean, int, etc.

Missing declarations, adding a boobe will do.

Why doesn't DS define a statement?