#region 操作驗證碼
private void CreateImage(string codes)
{
try
{
label1.Text = codes;
int iMapWidth = codes.Length * 21;
Bitmap map = new Bitmap(iMapWidth, 28); //建立圖檔背景
Graphics graph = Graphics.FromImage(map);
graph.Clear(Color.AliceBlue);//清除畫面,填充背景
graph.DrawRectangle(new Pen(Color.Black, 0), 0, 0, map.Width - 1, map.Height - 1);//畫一個邊框
graph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//模式 抗鋸齒
Random rand = new Random();
//背景噪點生成
Pen blackPen = new Pen(Color.LightGray, 0);
for (int i = 0; i < 50; i++)
{
int x = rand.Next(0, map.Width);
int y = rand.Next(0, map.Height);
graph.DrawRectangle(blackPen, x, y, 1, 1);
}
//驗證碼旋轉,防止機器識别
char[] chars = codes.ToCharArray();//拆散字元串成單字元數組
//文字距中
StringFormat format = new StringFormat(StringFormatFlags.NoClip);
format.Alignment = StringAlignment.Center;
format.LineAlignment = StringAlignment.Center;
//定義顔色
Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
//定義字型
string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋體" };
for (int i = 0; i < chars.Length; i++)
{
int cindex = rand.Next(7);
int findex = rand.Next(5);
Font f = new System.Drawing.Font(font[findex], 13, System.Drawing.FontStyle.Bold);//字型樣式(參數2為字型大小)
Brush b = new System.Drawing.SolidBrush(c[cindex]);
graph.DrawString(chars[i].ToString(), f, b, i * 16 + 8, 15, format);
}
this.pictureBox1.Image = map;
}
catch (ArgumentException ex)
{
MessageBox.Show("建立圖檔驗證碼錯誤,錯誤原因:" + ex.Message.ToString());
}
}
/// <summary>
/// 得到驗證碼
/// </summary>
/// <returns></returns>
private string getCode()
{
string code = "";
int j;
Random r = new Random();
for (int i = 0; i < 4; i++)
{
j = r.Next();
if (j % 3 == 0)
{
code += (char)('A' + (char)(j % 26));
}
else
{
code += (char)('0' + (char)(j % 10));
}
}
return code;
}
/// <summary>
/// 加載驗證碼
/// </summary>
private void LoadCode()
{
string right_code = getCode();
CreateImage(right_code);
}
#endregion