C#多重条件查询

   String sql = "select * from cus_mis_readft5_range ";//要留个空格最后

    
         List<String> whereList = new List<string>();  //存放条件的
    
         List<OracleParameter> parameters = new List<OracleParameter>(); //存放参数的
    
         if(!String.IsNullOrEmpty(comboBox1.Text)){
    
             whereList.Add(" range_type like :a "); //两边各空一格
    
             OracleParameter paramater = new OracleParameter();
    
             paramater.ParameterName = ":a";//设置参数
    
             paramater.Value = "%" + comboBox1.Text + "%"; //给参数赋值
    
             parameters.Add(paramater);、、添加
    
         }
    
         if (!String.IsNullOrEmpty(comboBox2.Text)) {
    
  
    
             whereList.Add(" range_name like :b "); //两边各空一格
    
             OracleParameter paramater = new OracleParameter();
    
             paramater.ParameterName = ":b";//设置参数
    
             paramater.Value = "%" + comboBox2.Text + "%";//给参数赋值
    
             parameters.Add(paramater);//添加
    
         }
    
         if (whereList.Count > 0) {
    
             sql += "where" + string.Join("and", whereList); //用and为间隔进行拼接sql字符串
    
         }