How to check for special characters in a string?

Question

How can I check whether there is a special character in my string when my input stored in a pointer? I tried this code but it seems that it will only check for the first char and not the whole string.

void EmployeeDetails(int count, account_s record[count]){  /* Function to get employee details */
    
    int i;
    char ch;
    EmployeeName: 
    for(i = 0; i < count; i++){ // count here is the amount of employee from main function      
        
        printf("\nEnter employee name: "); 
        scanf("%s", record[i].EmpName);
        ch = record[i].EmpName[i];
     
        if((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')){

Answer 1

You probably want something like this:

void EmployeeDetails(int count, account_s record[count]){  /* Function to get employee details */
    
    int i;
    EmployeeName: 
    for(i = 0; i < count; i++){ // count here is the amount of employee from main function      
        
        printf("\nEnter employee name: "); 
        scanf("%s", record[i].EmpName);

        for (j = 0; j < strlen(record[i].EmpName); j++)
        {
          char ch = record[i].EmpName[j];
          if((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')){
            ...
        }

But the best way is to use on of the standard functions and replace if((ch >= 'a' with this:

if (!isalpha(ch)) {
   ...

Even better: outsource the checking if there are special characters in the string to a function:

Replace the whole for (j = loop with:

   if (ContainsSpecialChars(record[i].EmpName)) {
      ...

with ContainsSpecialChars being:

int ContainsSpecialChars(const char name[])
{
   // Returns 1 if name contains a special character. Otherwise returns 0.
   //
   // I let you write this as an exercise
}

Don't forget #include <ctypes.h> for the isalpha function.