Winform快速导出

public static void ExportExcel(DataGridView DataGridView01)
{
Stream stream = null;
StreamWriter writer = null;
SaveFileDialog dialog = new SaveFileDialog {
Filter = "Execl files (*.xls)|*.xls",
FilterIndex = 0,
RestoreDirectory = true,
CreatePrompt = true,
Title = "Export Excel File To"
};
if (DialogResult.OK == dialog.ShowDialog())
{
try
{
stream = dialog.OpenFile();
writer = new StreamWriter(stream, Encoding.GetEncoding(0));
string str = "";
for (int i = 0; i < DataGridView01.ColumnCount; i++)
{
if (i > 0)
{
str = str + " ";
}
str = str + DataGridView01.Columns[i].HeaderText;
}
writer.WriteLine(str);
int columnCount = DataGridView01.ColumnCount;
for (int j = 0; j < DataGridView01.Rows.Count; j++)
{
string str2 = "";
for (int k = 0; k < columnCount; k++)
{
if (k > 0)
{
str2 = str2 + " ";
}
if (k > 0x16)
{
}
if (DataGridView01.Rows[j].Cells[k].Value == null)
{
str2 = str2 ?? "";
}
else
{
str2 = str2 + DataGridView01.Rows[j].Cells[k].Value.ToString();
}
}
writer.WriteLine(str2);
}
writer.Close();
stream.Close();
}
catch (Exception exception)
{
MessageBox.Show("导出文件时出错,文件可能正被打开！ " + exception.Message);
}
finally
{
writer.Close();
stream.Close();
}
MessageBox.Show("保存成功", "提示", MessageBoxButtons.OK);
}
}

 //

如果 ?? 运算符的左操作数非 null，该运算符将返回左操作数，否则返回右操作数。