C#里面怎样设置richTextBox的行间距

近日在做项目时，需要将查询查来的数据在richTextBox里面分行显示，但是richTextBox默认的行间距很小，显示的数据看着很挤，视觉效果差，后查找资料，发现通过以下方法能设置richTextBox的行间距。

 

using System.Runtime.InteropServices;

里面粘贴这些代码

public const int WM_USER = 0x0400;
public const int EM_GETPARAFORMAT = WM_USER + 61;
public const int EM_SETPARAFORMAT = WM_USER + 71;
public const long MAX_TAB_STOPS = 32;
public const uint PFM_LINESPACING = 0x00000100;
[StructLayout(LayoutKind.Sequential)]

private struct PARAFORMAT2
{
　　public int cbSize;
　　public uint dwMask;
　　public short wNumbering;
　　public short wReserved;
　　public int dxStartIndent;
　　public int dxRightIndent;
　　public int dxOffset;
　　public short wAlignment;
　　public short cTabCount;

　　[MarshalAs(UnmanagedType.ByValArray, SizeConst = 32)]
　　public int[] rgxTabs;
　　public int dySpaceBefore;
　　public int dySpaceAfter;
　　public int dyLineSpacing;
　　public short sStyle;
　　public byte bLineSpacingRule;
　　public byte bOutlineLevel;
　　public short wShadingWeight;
　　public short wShadingStyle;
　　public short wNumberingStart;
　　public short wNumberingStyle;
　　public short wNumberingTab;
　　public short wBorderSpace;
　　public short wBorderWidth;
　　public short wBorders;
}

[DllImport("user32", CharSet = CharSet.Auto)]
private static extern IntPtr SendMessage(HandleRef hWnd, int msg, int wParam, ref PARAFORMAT2 lParam);

//button1_Click里面的代码是设置行间距的代码，可通过设置fmt.dyLineSpacing的值来修改行间距的大小。

private void button1_Click(object sender, EventArgs e)
{
　　PARAFORMAT2 fmt = new PARAFORMAT2();

　　fmt.cbSize = Marshal.SizeOf(fmt);
　　fmt.bLineSpacingRule = 4;
　　fmt.dyLineSpacing = 40 * (9 + 3);//((int)richTextBox1.Font.Size) * 20 * ((int)ud.Value);
　　fmt.dwMask = PFM_LINESPACING;

　　SendMessage(new HandleRef(this.richTextBox1, richTextBox1.Handle), EM_SETPARAFORMAT, 0, ref fmt);

}