.NET Regex, only numeric, no spaces

Question

I'm looking for a regular expression that accepts only numerical values and no spaces. I'm currently using: ``` ^(0|[1-9][0-9]*)$ ``` which works fine, but it accepts values that consist ONLY of spaces. What is wrong with it?

Accepted Answer

The reason why is that `*` will accept 0 or more. A purely empty string has 0 numbers and hence meets the requirements. You need 1 or more so use `+` instead.

```
^(0|[1-9][0-9]+)$
```

EDIT

Here is Andrews more robust and simpler solution.

```
^\d+$
```

.NET Regex, only numeric, no spaces

Solution

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