C# 判断两张图片是否一致的快速方法

#region 判断图片是否一致
/// <summary>
/// 判断图片是否一致
/// </summary>
/// <param name="img">图片一</param>
/// <param name="bmp">图片二</param>
/// <returns>是否一致</returns>
public bool issameimg(bitmap img, bitmap bmp)
{
//大小一致
if (img.width == bmp.width && img.height == bmp.height)
{
//将图片一锁定到内存
bitmapdata imgdata_i = img.lockbits(new rectangle(0, 0, img.width, img.height), imagelockmode.readonly, pixelformat.format24bpprgb);
intptr ipr_i = imgdata_i.scan0;
int length_i = imgdata_i.width * imgdata_i.height * 3;
byte[] imgvalue_i = new byte[length_i];
marshal.copy(ipr_i, imgvalue_i, 0, length_i);
img.unlockbits(imgdata_i);
//将图片二锁定到内存
bitmapdata imgdata_b = img.lockbits(new rectangle(0, 0, img.width, img.height), imagelockmode.readonly, pixelformat.format24bpprgb);
intptr ipr_b = imgdata_b.scan0;
int length_b = imgdata_b.width * imgdata_b.height * 3;
byte[] imgvalue_b = new byte[length_b];
marshal.copy(ipr_b, imgvalue_b, 0, length_b);
img.unlockbits(imgdata_b);
//长度不相同
if (length_i != length_b)
{
return false;
}
else
{
//循环判断值
for (int i = 0; i < length_i; i++)
{
//不一致
if (imgvalue_i[i] != imgvalue_b[i])
{
return false;
}
}
return true;
}
}
else
{
return false;
}
}
#endregion