// Thanks to https://github.com/andreypopp/react-textarea-autosize/ /** * calculateNodeHeight(uiTextNode, useCache = false) */ const HIDDEN_TEXTAREA_STYLE = ` min-height:0 !important; max-height:none !important; height:0 !important; visibility:hidden !important; overflow:hidden !important; position:absolute !important; z-index:-1000 !important; top:0 !important; right:0 !important `; const SIZING_STYLE = [ 'letter-spacing', 'line-height', 'padding-top', 'padding-bottom', 'font-family', 'font-weight', 'font-size', 'font-variant', 'text-rendering', 'text-transform', 'width', 'text-indent', 'padding-left', 'padding-right', 'border-width', 'box-sizing', ]; export interface NodeType { sizingStyle: string; paddingSize: number; borderSize: number; boxSizing: string; } const computedStyleCache: { [key: string]: NodeType } = {}; let hiddenTextarea: HTMLTextAreaElement; export function calculateNodeStyling(node: HTMLElement, useCache = false) { const nodeRef = (node.getAttribute('id') || node.getAttribute('data-reactid') || node.getAttribute('name')) as string; if (useCache && computedStyleCache[nodeRef]) { return computedStyleCache[nodeRef]; } const style = window.getComputedStyle(node); const boxSizing = style.getPropertyValue('box-sizing') || style.getPropertyValue('-moz-box-sizing') || style.getPropertyValue('-webkit-box-sizing'); const paddingSize = parseFloat(style.getPropertyValue('padding-bottom')) + parseFloat(style.getPropertyValue('padding-top')); const borderSize = parseFloat(style.getPropertyValue('border-bottom-width')) + parseFloat(style.getPropertyValue('border-top-width')); const sizingStyle = SIZING_STYLE.map(name => `${name}:${style.getPropertyValue(name)}`).join(';'); const nodeInfo: NodeType = { sizingStyle, paddingSize, borderSize, boxSizing, }; if (useCache && nodeRef) { computedStyleCache[nodeRef] = nodeInfo; } return nodeInfo; } export default function calculateNodeHeight( uiTextNode: HTMLTextAreaElement, useCache = false, minRows: number | null = null, maxRows: number | null = null, ) { if (!hiddenTextarea) { hiddenTextarea = document.createElement('textarea'); document.body.appendChild(hiddenTextarea); } // Fix wrap="off" issue // https://github.com/ant-design/ant-design/issues/6577 if (uiTextNode.getAttribute('wrap')) { hiddenTextarea.setAttribute('wrap', uiTextNode.getAttribute('wrap') as string); } else { hiddenTextarea.removeAttribute('wrap'); } // Copy all CSS properties that have an impact on the height of the content in // the textbox const { paddingSize, borderSize, boxSizing, sizingStyle } = calculateNodeStyling( uiTextNode, useCache, ); // Need to have the overflow attribute to hide the scrollbar otherwise // text-lines will not calculated properly as the shadow will technically be // narrower for content hiddenTextarea.setAttribute('style', `${sizingStyle};${HIDDEN_TEXTAREA_STYLE}`); hiddenTextarea.value = uiTextNode.value || uiTextNode.placeholder || ''; let minHeight = Number.MIN_SAFE_INTEGER; let maxHeight = Number.MAX_SAFE_INTEGER; let height = hiddenTextarea.scrollHeight; let overflowY: any; if (boxSizing === 'border-box') { // border-box: add border, since height = content + padding + border height = height + borderSize; } else if (boxSizing === 'content-box') { // remove padding, since height = content height = height - paddingSize; } if (minRows !== null || maxRows !== null) { // measure height of a textarea with a single row hiddenTextarea.value = ' '; const singleRowHeight = hiddenTextarea.scrollHeight - paddingSize; if (minRows !== null) { minHeight = singleRowHeight * minRows; if (boxSizing === 'border-box') { minHeight = minHeight + paddingSize + borderSize; } height = Math.max(minHeight, height); } if (maxRows !== null) { maxHeight = singleRowHeight * maxRows; if (boxSizing === 'border-box') { maxHeight = maxHeight + paddingSize + borderSize; } overflowY = height > maxHeight ? '' : 'hidden'; height = Math.min(maxHeight, height); } } return { height, minHeight, maxHeight, overflowY }; }