以下代码报错。跪求大虾赐教！
string str=comboBox1.Text.trim();
"select RTRIM({0}.dbo.ADMMF.MF002) from {0}.dbo.ADMMF WHERE {0}.dbo.ADMMF.MF004='1001' AND
{0}.dbo.ADMMF.MF001 <>'**********' AND {0}.dbo.ADMMF.MF001='" + textBox2.Text + "' AND {0}.dbo.ADMMF.MF001 IN ('001','002')"

"select RTRIM( "+ str +".dbo.ADMMF.MF002) from "+ str +".dbo.ADMMF WHERE "+ str +".dbo.ADMMF.MF004='1001' AND
"+ str +".dbo.ADMMF.MF001 <>'**********' AND "+ str +".dbo.ADMMF.MF001='" + textBox2.Text + "' AND "+ str +".dbo.ADMMF.MF001 IN ('001','002')"

不对，这种写法跟我那样报一样的错误！