设置textView的行间距

1.如果只是静态显示textView的内容为设置的行间距，执行如下代码：
// textview 改变字体的行间距 
   
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init]; 
    
paragraphStyle.lineSpacing = 10;// 字体的行间距 
  
NSDictionary *attributes = @{NSFontAttributeName:[UIFont systemFontOfSize:15],NSParagraphStyleAttributeName:paragraphStyle}; 
    
textView.attributedText = [[NSAttributedString alloc] initWithString:@"输入你的内容" attributes:attributes];
 
2.如果是想在输入内容的时候就按照设置的行间距进行动态改变，那就需要将上面代码放到textView的delegate方法里
-(void)textViewDidChange:(UITextView *)textView
{
// textview 改变字体的行间距
   NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
   paragraphStyle.lineSpacing = 20;// 字体的行间距
    
   NSDictionary *attributes = @{
                                  NSFontAttributeName:[UIFont systemFontOfSize:15],
                                  NSParagraphStyleAttributeName:paragraphStyle
                               };
   textView.attributedText = [[NSAttributedString alloc] initWithString:textView.text attributes:attributes];
 
}