Incubator-echarts: echarts.format.truncateText

[baixiaoji]

Other comments [其他信息]

echarts.format.truncateText 像这一类的AP接口文档里好像没有

[pissang]

这个接口暂时还没对外开发

[baixiaoji]

可是感觉这部分的功能都很好用，但是没有明确的文档看看

[TheoXiong]

echarts.format.truncateText(name,  40,  '14px Microsoft Yahei',  '…')

同问，第二个参数是什么意思，好像并不是字符串最大长度

[TheoXiong]

查看源码，大概明白了，第二个参数应该是文本宽度（单位：像素px）。

/**
 * Show ellipsis if overflow.
 *
 * @public
 * @param  {string} text
 * @param  {string} containerWidth
 * @param  {string} font
 * @param  {number} [ellipsis='...']
 * @param  {Object} [options]
 * @param  {number} [options.maxIterations=3]
 * @param  {number} [options.minChar=0] If truncate result are less
 *                  then minChar, ellipsis will not show, which is
 *                  better for user hint in some cases.
 * @param  {number} [options.placeholder=''] When all truncated, use the placeholder.
 * @return {string}
 */
function truncateText(text, containerWidth, font, ellipsis, options) {
    if (!containerWidth) {
        return '';
    }

    var textLines = (text + '').split('\n');
    options = prepareTruncateOptions(containerWidth, font, ellipsis, options);

    // FIXME
    // It is not appropriate that every line has '...' when truncate multiple lines.
    for (var i = 0, len = textLines.length; i < len; i++) {
        textLines[i] = truncateSingleLine(textLines[i], options);
    }

    return textLines.join('\n');
}


/**
 * @public
 * @param {string} text
 * @param {string} font
 * @return {Object} width
 */
function measureText(text, font) {
    return methods$1.measureText(text, font);
}

// Avoid assign to an exported variable, for transforming to cjs.
methods$1.measureText = function (text, font) {
    var ctx = getContext();
    ctx.font = font || DEFAULT_FONT$1;
    return ctx.measureText(text);
};