下面的代码复制了查询选择器目标的所有相关节点，复制了它们在屏幕上看到的样式，因为许多用于css选择器目标的父元素将会丢失。如果有很多带有很多样式的子节点，这将导致一些延迟。

理想情况下，你应该有一个打印样式表，但这是为用例，没有打印样式表插入，你希望打印在屏幕上看到。

如果您在此页的浏览器控制台中复制以下项目，它将打印此页上的所有代码片段。

+function() {
    /**
     * copied from  https://stackoverflow.com/questions/19784064/set-javascript-computed-style-from-one-element-to-another
     * @author Adi Darachi https://stackoverflow.com/users/2318881/adi-darachi
     */
    var copyComputedStyle = function(from,to){
        var computed_style_object = false;
        //trying to figure out which style object we need to use depense on the browser support
        //so we try until we have one
        computed_style_object = from.currentStyle || document.defaultView.getComputedStyle(from,null);

        //if the browser dose not support both methods we will return null
        if(!computed_style_object) return null;

            var stylePropertyValid = function(name,value){
                        //checking that the value is not a undefined
                return typeof value !== 'undefined' &&
                        //checking that the value is not a object
                        typeof value !== 'object' &&
                        //checking that the value is not a function
                        typeof value !== 'function' &&
                        //checking that we dosent have empty string
                        value.length > 0 &&
                        //checking that the property is not int index ( happens on some browser
                        value != parseInt(value)

            };

        //we iterating the computed style object and compy the style props and the values
        for(property in computed_style_object)
        {
            //checking if the property and value we get are valid sinse browser have different implementations
                if(stylePropertyValid(property,computed_style_object[property]))
                {
                    //applying the style property to the target element
                        to.style[property] = computed_style_object[property];

                }   
        }   

    };


    // Copy over all relevant styles to preserve styling, work the way down the children tree.
    var buildChild = function(masterList, childList) {
        for(c=0; c<masterList.length; c++) {
           var master = masterList[c];
           var child = childList[c];
           copyComputedStyle(master, child);
           if(master.children && master.children.length > 0) {
               buildChild(master.children, child.children);
           }
        }
    }

    /** select elements to print with query selector **/
    var printSelection = function(querySelector) {
        // Create an iframe to make sure everything is clean and ordered.
        var iframe = document.createElement('iframe');
        // Give it enough dimension so you can visually check when modifying.
        iframe.width = document.width;
        iframe.height = document.height;
        // Add it to the current document to be sure it has the internal objects set up.
        document.body.append(iframe);

        var nodes = document.querySelectorAll(querySelector);
        if(!nodes || nodes.length == 0) {
           console.error('Printing Faillure: Nothing to print. Please check your querySelector');
           return;
        }

        for(i=0; i < nodes.length; i++) {

            // Get the node you wish to print.
            var origNode = nodes[i];

            // Clone it and all it's children
            var node = origNode.cloneNode(true);

            // Copy the base style.
            copyComputedStyle(origNode, node);

            if(origNode.children && origNode.children.length > 0) {
                buildChild(origNode.children, node.children);
            }

            // Add the styled clone to the iframe. using contentWindow.document since it seems the be the most widely supported version.

            iframe.contentWindow.document.body.append(node);
        }
        // Print the window
        iframe.contentWindow.print();

        // Give the browser a second to gather the data then remove the iframe.
        window.setTimeout(function() {iframe.parentNode.removeChild(iframe)}, 1000);
    }
window.printSelection = printSelection;
}();
printSelection('.default.prettyprint.prettyprinted')

这应该可以工作:

function printDiv(divName) {
     var printContents = document.getElementById(divName).innerHTML;
     var originalContents = document.body.innerHTML;
     document.body.innerHTML = printContents;
     window.print();
     document.body.innerHTML = originalContents;
}

我编写了一个插件来解决这种情况。我对现有的插件不满意，开始做一些更广泛/可配置的东西。

https://github.com/jasonday/printThis

function printdiv(printdivname) {
    var headstr = "<html><head><title>Booking Details</title></head><body>";
    var footstr = "</body>";
    var newstr = document.getElementById(printdivname).innerHTML;
    var oldstr = document.body.innerHTML;
    document.body.innerHTML = headstr+newstr+footstr;
    window.print();
    document.body.innerHTML = oldstr;
    return false;
}

这将打印您想要的div区域，并将内容设置为原来的内容。Printdivname是要打印的div。

使用Jquery，简单地使用这个函数:

<script>
function printContent(el){
var restorepage = $('body').html();
var printcontent = $('#' + el).clone();
$('body').empty().html(printcontent);
window.print();
$('body').html(restorepage);
}
</script>

你的打印按钮看起来是这样的:

<button id="print" onclick="printContent('id name of your div');" >Print</button>

编辑:如果你有表单数据，你需要保留，克隆不会复制，所以你只需要抓取所有的表单数据，并在恢复后替换它如下:

<script>
function printContent(el){
var restorepage = $('body').html();
var printcontent = $('#' + el).clone();
var enteredtext = $('#text').val();
$('body').empty().html(printcontent);
window.print();
$('body').html(restorepage);
$('#text').html(enteredtext);
}
</script>
<textarea id="text"></textarea>

只需使用PrintJS

let printjs = document.createElement("script");
printjs.src = "https://printjs-4de6.kxcdn.com/print.min.js";
document.body.appendChild(printjs);

printjs.onload = function (){
    printJS('id_of_div_you_want_to_print', 'html');
}