我有这行代码:CGContextSelectFont(context,"Courier",[storedTextSizefloatValue],kCGEncodingFontSpecific);CGContextSetTextDrawingMode(context,kCGTextFill);CGContextSetTextPosition(context,0.0f,round([storedTextSizefloatValue]/4.0f));CGContextShowText(context,[stringUTF8String],strlen([stringUTF8String]))