CTYPE_DIGIT

Check for numeric character(s)

The tested string.

Note: If an integer between -128 and 255 inclusive is provided, it is interpreted as the ASCII value of a single character (negative values have 256 added in order to allow characters in the Extended ASCII range). Any other integer is interpreted as a string containing the decimal digits of the integer.

Returns TRUE if every character in the string text is a decimal digit, FALSE otherwise.

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