Facing Problem in Searching Using Multiple Columns

Hello,

Why not construct the SQL dynamically. If a value is not specified in textbox then you may not want to include that in where condition of your sql. Formulate your query as shown below.
<pre lang="C#">StringBuilder sb = new StringBuilder("SELECT * FROM beneficiarydetails ", 1024);
int len - sb.Length;
if (!String.IsNullOrEmpty(textBox1.Text))
{
    sb.append(" WHERE AccountNo = ");
        .append(textBox1.Text)
        .append("'";
}
if (!String.IsNullOrEmpty(textBox2.Text))
{
    if (sb.length == len)
    {
        sb.append(" WHERE );
    }
    else
    {
        sb.append(" AND ");
    }
    sb.append(" empname = '")
        .append(textBox2.Text.Trim())
        .append("'");
}
if (!String.IsNullOrEmpty(textBox3.Text))
{
    if (sb.length == len)
    {
        sb.append(" WHERE );
    }
    else
    {
        sb.append(" AND ");
    }
    sb.append(" ddocode = '")
        .append(textBox3.Text)
        .append("'");
}