Value was either too large or too small for an Int32 [duplicate]

问题:

Possible Duplicate:
What is the maximum value for a int32?

Mobileno = Convert.ToInt32(txmobileno.Text); 

error i amm getting while inserting in to database

回答1:

Why on earth would you use an integer of any type to store a phone number?

You can't meaningfully do any arithmetics on one and you lose all leading zeroes.

Use a string instead.

回答2:

An integer (Int32) is limited in the values it can store since it "only" uses 32 bits. It can store a value between 2,147,483,647 and -2,147,483,648. (More information on MSDN)

The value represented by the txmobileno.Text, is too large or too small.

Looking at the name txmobileno is probably a mobile phone number. This kind of numbers have too much digits to store in an int32. Also a phone number tends to start with a 0 or 00 or + (international). There's no way of storing this kind of information in an integer (or another number type). Just store them in a string.

回答3:

As others have pointed out, storing a phone number as an integer is a mistake.

• You lose the ability to store characters and whitespace, for example country codes - "+44 (0800) 12345".
• There is no logical reason to store it as an integer - would you ever need to do arithmetic on two telephone numbers? Does it make sense to add two phone numbers together?
• Leading zeros will be lost - (0800 12345) will become (80012345).
• Storing it as a string allows you to do regex validation on the user input.

Having said that, the original question does raise some points which should be made:

• Prefer Int32.TryParse instead of Convert.ToInt32 when the source value is a string.
• When dealing with values which may potentially overflow - enclose the code in a checked { ... } block.

文章来源: Value was either too large or too small for an Int32 [duplicate]