Can I limit number of new lines in multiline asp:TextBox

Question

我可以使用 javascript 或 C# 在多行 asp:TextBox 中限制为仅 3 个新行吗

Answer 1

only by setting Rows property to 3 you can achieve this like this:

<asp:TextBox ID="txtBox1" runat="server" Rows="3" TextMode="MultiLine"></asp:TextBox>

use javascript:

function validate(e, max,maxchar)
{
var text = e.value.replace(/\s+$/g,""); var split = text.split("\n");
if (split.length <= max && text.length <=maxchar)
{
  return true;
}
else if (split.length >= max || e.value.length >=maxchar)
{
 return false;
}
}
 <asp:TextBox ID="txtBox1" runat="server" TextMode="MultiLine" Rows="3" onkeypress="return validate(this,max_number,maxchar_number)"/>

change the value of max_number and maxchar_number based on your requirement.