ConstructionOperation/web/maintain/report/rpt_tpl_preview.html

<div class="form-view col-lg-7 p-0">
    <div class="main-data-h" style="position:relative">
        <div class="sub-button p-2">
            <button class="btn btn-primary" onclick="tplHelper.saveRptTpl()">保存</button>
            <button class="btn btn-primary" onclick="preview_util.getPreviewPage($('#tplCanvas')[0], zTreeOprObj.getRefTpl()) ">预览</button>
        </div>
        <div class="main-data">
            <canvas id="tplCanvas" height="800" width="900"></canvas>
        </div>
    </div>
</div>