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table合并单元格
function uniteTdCells(tableId){var table = document.getElementById(tableId);for (let i = 0; i < table.rows.length; i++) {for (let c = 0; c < table.rows[i].cells.length; c++) {if (c == 0 || c == 1 || c == 2 || c == 3) { //选择要合并的列序数,去掉默认全部合并for (let j = i + 1; j < table.rows.length; j++) {let cell1 = table.rows[i].cells[c].innerHTML;let cell2 = table.rows[j].cells[c].innerHTML;if (cell1 == cell2) {table.rows[j].cells[c].style.display = 'none';table.rows[j].cells[c].style.verticalAlign = 'middle';table.rows[i].cells[c].rowSpan++;} else {table.rows[j].cells[c].style.verticalAlign = 'middle'; //合并后剩余项内容自动居中break;};}}}}};