How to convert string to int in C#

Question

Sorry, I am new to C#. I am getting a value for quantity from sqlserver. Usually, it comes as a decimal string. For example as "6.00". I have to store it as an int in a C# variable. I am doing the following which worked in a few rows of data I have tested:

int newVal = 
    Convert.ToInt32(Convert.ToDecimal(drUsers["quantity"].ToString()));

If I convert directly to int without converting it first to decimal then it throws "Input not in correct format" error. Is there a better way of doing it, especially to handle data errors such as null coming from the database.

Thanks

If it's already a number in the database, you might just be able to cast it. Have you tried that? — cost
– cost, Commented Mar 13, 2019 at 18:39
TryParse will return false if the conversion fails, which will allow you to handle invalid data without throwing an exception. — littlerufe
– littlerufe, Commented Mar 13, 2019 at 18:53

Dortimer · Accepted Answer · 2019-03-13 19:06:38Z

1

If you know for sure that the value you're getting is going to be a decimal you could just use

int newVal = (int)Decimal.Parse(drUsers["quantity"]);

If you want to be safe and program defensively, I'd suggest using Decimal.TryParse() something along the lines of:

decimal foo = 0;
int newVal = 0;

if(Decimal.TryParse(drUsers["quantity"], out foo) {
    newVal = (int)foo;
} else {
    //handle error
}

EDIT: switched double to decimal, but I think the choice depends on the accuracy you need with the decimal. Database types don’t always match 1:1 with types in c# so either should be okay.

edited Mar 13, 2019 at 19:06

answered Mar 13, 2019 at 18:42

Dortimer

6178 silver badges29 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

cost Over a year ago

If it's already a Decimal, wouldn't it be safer to use Decimal.Parse?

Dortimer Over a year ago

It depends on what the data looks like from the database. If it's a short decimal like "4.243" then Double will suffice, but if it's something "extreme" like "4.2342353252234232423435143621345435343234234" you'll probably want to use Decimal.Parse for higher accuracy. net-informations.com/q/faq/float.html here's a little more information on the differences.

hardkoded · Accepted Answer · 2019-03-13 18:36:16Z

1

I would avoid the ToSring(). You can get the quantity as a decimal using the Field method.

Convert.ToInt32(drUsers.Field<decimal>("quantity"));

answered Mar 13, 2019 at 18:36

hardkoded

22k3 gold badges64 silver badges78 bronze badges

Collectives™ on Stack Overflow

How to convert string to int in C#

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related