How does php directly display office documents and PDF files on the webpage?

How does php directly display office documents and PDF files on a webpage? It is displayed directly on the webpage and arranged in the correct way, just as it is displayed on the client! & Nbsp; I used & lt; ahref = & quot; & gt; & lt;/a & gt; link, under mac, safari can be directly displayed on the webpage, but in windo php, how can I directly display office documents and PDF files on the webpage?
It is displayed directly on the webpage and arranged in the correct way, just as it is displayed on the client!
I used a link. on a mac, safari can be directly displayed on a webpage. However, when I use ie in windows, I am prompted to open or save it, open the client directly!
I want to click to display it directly on the webpage. how can this problem be achieved?

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In fact, chrome under win can also be opened directly, which is related to the browser. the old guy like ie may have to install plug-ins.
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The browser can only open files that it can recognize. if a download dialog box appears, the browser does not recognize the files.
You need to install the corresponding program or plug-in
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Discussion

The browser can only open files that it can recognize. if a download dialog box appears, the browser does not recognize the files.
You need to install the corresponding program or plug-in

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To unify the performance of all browsers, there is only one way to convert these files into HTML format on the server side.