如何在asp圖表控件中顯示錯誤消息到圖表中

Question

我有一個圖表，我必須將消息顯示爲「無數據存在」，此時rows.count == 0 否則通常爲條形圖。

我可以知道如何顯示該消息。

在此先感謝。

Answer 1

試試這個：

protected void ChartExample_DataBound(object sender, EventArgs e) 
{ 
    // If there is no data in the series, show a text annotation 
    if(ChartExample.Series[0].Points.Count == 0) 
    { 
     System.Web.UI.DataVisualization.Charting.TextAnnotation annotation = 
      new System.Web.UI.DataVisualization.Charting.TextAnnotation(); 
     annotation.Text = "No data for this period"; 
     annotation.X = 5; 
     annotation.Y = 5; 
     annotation.Font = new System.Drawing.Font("Arial", 12); 
     annotation.ForeColor = System.Drawing.Color.Red; 
     ChartExample.Annotations.Add(annotation); 
    } 
} 

感謝