Php directly prints related questions (the select printer dialog box is not displayed)

Php direct printing problem (do not pop up the select printer dialog box) php can not print, to call js printing, but checked online, so the code is to pop up the select printer dialog box, even if you delete the printer to the default one, how can you click the button to print it directly without selecting a printer? the customer uses the browser you developed, there may also be a php direct printing problem (the select printer dialog box is not displayed)
Php cannot print. js printing is required, but the code is checked online. the select printer dialog box is displayed, even if the printer is deleted to the default one, how can I click the button and print it directly without selecting a printer?

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The customer may also use your browser.
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I have encountered this problem. it seems that print () using JS is like this. there is no way... I have checked that some controls can be used to implement the functions you mentioned, but it seems to be charged... so LZ just makes up a point ..
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This actually involves a security issue.
In fact, the landlord may need to consider two aspects:
1. what are the roles of B and S in the B/S system.
2. is there a logic problem? for example, if the browser allows you to output a piece of code and print it directly, what completeness does the customer have?