我使用了标记，它起作用了:

 字符串 errorMessage = " ;

 for ( int  i =  0 ; i&lt ; 4; i ++){

errorMessage = errorMessage + "  + i + " </br>";

} literal.Text = errorMessage;

} 

谢谢
Jyotish

hi I want to dispaly the name of the items in seperate lines..
my code is :

if (!countForChildSupplier.Equals(SysXConsts.NONE))
               {
                   errorMessage = "Please reject these supplier changes as listed child supplier(s) is/are already mapped with other supplier(s)." + Environment.NewLine;
                   duplicateChildSuppliers.ForEach(item =>
                       {
                           errorMessage = errorMessage + item + Environment.NewLine;
                       });
                   errorMessage = errorMessage.Substring(SysXConsts.NONE, errorMessage.Length - SysXConsts.ONE);
                   errorMessage = errorMessage + "." + Environment.NewLine;
               }

but it is not working

I used the tag and it worked:

string errorMessage = "Please reject these supplier changes as listed child supplier(s) is/are already mapped with other supplier(s).</br>";

for(int i=0;i<4;i++){

errorMessage =errorMessage + "Item"+i+"</br>";

} literal.Text=errorMessage;

}

Thanks
Jyotish