Using /setblock, how do I set a command block with a prefilled command?

Question

Using /setblock, I'd like to set a command block with a command already pre-filled inside of it.

My current code looks like this, but it doesn't seem to work:

setblock <x> <y> <z> command_block {TileEntityData:{Command:"testfor @p[_=1]"}}

What's wrong with it, and what do I need to change?

Answer 1

You will need to do two things:

• Firstly, there are two other parts to the /setblock command that need to be present; the datavalue, and the method of handling the existing block, if any.
• Secondly, the data tag at the end should just be {Command: "testfor @p[_=1]"}, without the TileEntityData bit.

Thus, the resulting command should be along the lines of

/setblock <x> <y> <z> command_block 0 replace {Command:"testfor @p[_=1]"}

As proof, here's a shot of me using that command:

And here's the result: