How to get/change the name of a chart in Office scripts.
Not the title that appears on the chart,
The name of the graph as it appears in the name box (where cell addresses are displayed).
Operations
You must first get the target chart.
chart variable = workbook.getWorksheet("Sheet name").getCharts()[index];chart variable = workbook.getWorksheet("Sheet name").getChart("Chart name");This can also be done with the return value (variable) of the result added with addChart().
If the acquisition fails, the result is undefined.
The chart name specified to getChart() is displayed in the name box.
Get name
chart variable.getName(); 
When a chart is newly created or a chart is acquired by indexing with getCharts(), the chart name is not known, so this function is used when the chart name is needed.
Rename
chart variable.setName("Chart name after change"); 
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