Change the Textbox height?

You can set the MinimumSize and/or the MaximumSize properties of the textbox. This does not affect the size immediately, but when you resize the textbox in the forms designer, the size will automatically be adjusted to satisfy the minimum/maximum size constraints. This works even when Multiline is set to false and does not depend on the font size.

There are two ways to do this :

• Set the textbox's "multiline" property to true, in this case you don't want to do it so;
• Set a bigger font size to the textbox

I believe it is the only ways to do it; the bigger font size should automatically fit with the textbox

Go into yourForm.Designer.cs Scroll down to your textbox. Example below is for textBox2 object. Add this

this.textBox2.AutoSize = false;

and set its size to whatever you want

this.textBox2.Size = new System.Drawing.Size(142, 27);

Will work like a charm - without setting multiline to true, but only until you change any option in designer itself (you will have to set these 2 lines again). I think, this method is still better than multilining. I had a textbox for nickname in my app and with multiline, people sometimes accidentially wrote their names twice, like Thomas\nThomas (you saw only one in actual textbox line). With this solution, text is simply hiding to the left after each char too long for width, so its much safer for users, to put inputs.