Reading integer from gridview textbox

I am converting a string that is being read from a textbox in gridview

int numTC = Convert.ToInt32(((TextBox)r开发者_StackOverflow中文版ow.FindControl("numTC")).Text);

However it is returning the following exception:

Input string was not in a correct format.

Can anyone see anything wrong in the conversion?

Thanks

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Make Sure that your gridview can accept only numbers you can have a filterextender using ajax and I m sure u will do that what else you can do is to check whether you have a textbox is null or not using the Function given below

if(string.IsNullOrEmpty(((TextBox)Row.FindControl("numTC")).Text)) {}

((TextBox)GridViewname.Rows[e.RowIndex].FindControl("numTC")).Text;

and

use this extender or u can use javascript as well

If it is going inside the if statement that means the value is null

 if(!string.IsNullOrEmpty(((TextBox)row.FindControl("numTC")).Text)) {} 

I have used ! sign now it will go inside the if statement if there is some value in it. and try to convert this text into integer using try catch block if u get any exception you can take whatever action you want to. Let me know if it is complete

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It is obvious that the value of the returned in the "Text" property of the text box cannot be converted to inter, I guess you have to insure first that you are returning the correct textbox and that it contains a valid value before attempting the conversion.