参考链接:http://www.voidcn.com/article/p-pavzanbd-btm.html

使用DataTable.Select(string filterExpression),
或者DataView.RowFilter
设置过滤表达式

DataView dv = new DataView(dt);
dv.RowFilter = 列名称+” like ‘%” +查询内容 + “%’”;
dataGridView1.DataSource = dv;

或者 参考链接:https://blog.csdn.net/u010458948/article/details/102462169

string strTemp = “ like ‘%” + text + “%’” + “or like ‘%” + text + “%’”

  1.                       + "or *** like '%" + text + "%'" + "or *** like '%" + text + "%'";
  2.        DataRow[] drArr1 = dt.Select(strTemp);
  3.        DataTable dtNew = dt.Clone();
  4.        for (int i = 0; i < drArr1.Length; i++)
  5.        {
  6.            dtNew.ImportRow(drArr1[i]); //ImportRow 是复制
  7.        }

———————————————— 版权声明：本文为CSDN博主「蓝之赟」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/u010458948/article/details/102462169 当DataTable的列类型为Int类型时会出现: 无法在System.Int32和System.String上执行“Like”操作

需要改为:
dv.RowFilter = string.Format(“CONVERT({0}, System.String) like ‘%{1}%’”, 列名称, 查询内容);

原文:

c# – 无法在System.Int32和System.String上执行“Like”操作. DataGridView搜索和过滤

时间 2018-09-24 原文 https://stackoverflow.com/questions/22328392/cannot-perform-like-operation-on-system-int32-and-system-string-datagridview

我有一个表单,当我从ComboBox中选择一个列名,并在文本框中键入它时,它会过滤并在DataGridView中显示搜索的条件.当我搜索“引用”时,它是一个int数据类型,也是标识和主键.我收到错误消息： “Cannot perform ‘Like’ operation on System.Int32 and System.String.” 我的代码是 DataTable dt;

private void searchForm_Load(object sender, EventArgs e)

{

  1. SqlCeConnection con = new SqlCeConnection(@"Data Source=|DataDirectory|\LWADataBase.sdf;");
  3. SqlCeDataAdapter sda = new SqlCeDataAdapter("select * from customersTBL", con);
  5. dt = new DataTable();
  7. sda.Fill(dt);
  9. dataGridView1.DataSource = dt;
  11. comboSearch.Items.Add("[Reference]");
  13. comboSearch.Items.Add("[First Name]");
  15. comboSearch.Items.Add("[Surename]");
  17. comboSearch.Items.Add("[Address Line 1]");
  19. comboSearch.Items.Add("[Address Line 2]");
  21. comboSearch.Items.Add("[County]");
  23. comboSearch.Items.Add("[Post Code]");
  25. comboSearch.Items.Add("[Contact Number]");
  27. comboSearch.Items.Add("[Email Address]");

}

private void searchTxt_TextChanged(object sender, EventArgs e)

{

  1. if (comboSearch.SelectedItem == null)
  3. {
  5.     searchTxt.ReadOnly = true;
  7.     MessageBox.Show("Please select a search criteria");
  9. }
  17. else
  19. {
  21.     searchTxt.ReadOnly = false;
  23.     DataView dv = new DataView(dt);
  25.     dv.RowFilter = "" + comboSearch.Text.Trim() + "like '%" + searchTxt.Text.Trim() + "%'";
  27.     dataGridView1.DataSource = dv;
  31. }

}

将数字转换为过滤器内的字符串：

dv.RowFilter = string.Format(“CONVERT({0}, System.String) like ‘%{1}%’”,

  1.                          comboSearch.Text.Trim(), searchTxt.Text.Trim());