javascript - Printing problem using websocket to connect printer through js

Use websocket to connect to the printer through js for printing. It is known that the printer port is open by default, through PHP code

<code>$s = fsockopen("192.168.1.122", 8081,$errno, $errstr, 30);
 fwrite($s,"abcjiuejseeeeeeeee2222222222ss");</code>

It is okay to print like this, but only the header information is printed through the websocket connection through JS. What is the situation?

js code is:

<code>ws = new WebSocket("ws://192.168.1.122:8081/");
console.log(ws);
ws.onopen = function (e) {
    console.log(e);
    console.log("连接成功");
    ws.send('2222222222222222222222222222');
};
ws.onclose = function(e) {
    console.log("连接关闭");
};
ws.onerror = function(e) {
    console.log("出现错误");
};</code>

js cannot be entered here ws.open

Reply content:

Use websocket to connect to the printer through js for printing. It is known that the printer port is open by default, through PHP code

<code>$s = fsockopen("192.168.1.122", 8081,$errno, $errstr, 30);
 fwrite($s,"abcjiuejseeeeeeeee2222222222ss");</code>

It is possible to print like this, but only the header information is printed through the JS websocket connection. What is the situation?

js code is:

<code>ws = new WebSocket("ws://192.168.1.122:8081/");
console.log(ws);
ws.onopen = function (e) {
    console.log(e);
    console.log("连接成功");
    ws.send('2222222222222222222222222222');
};
ws.onclose = function(e) {
    console.log("连接关闭");
};
ws.onerror = function(e) {
    console.log("出现错误");
};</code>

js cannot be entered here ws.open

<code>$s = fsockopen("192.168.1.122", 8081,$errno, $errstr, 30);</code>

<code>ws = new WebSocket("ws://192.168.10.120:8081/");</code>

Brother, have you noticed any subtle differences?
192.168.1.122
192.168.10.120

Websocket is based on the need for handshake verification. You can take a look at the three handshakes of the Tcp protocol and the communication between websocket and PHP socket